KSA National Land Suitability — 26 Diagnostic Factors

Select a diagnostic factor to view per-crop tolerance thresholds, Capability cross-reference, and assessment method.

The routing rule — how a hectare reaches a suitability class

STEP 1

Capability returns a class and subclass for the hectare.

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STEP 2

The capability-by-sector matrix routes the hectare to candidate sectors.

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STEP 3 — THIS PAGE

This matrix routes each candidate sector to its production systems and their governing factors.

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STEP 4

The by-crop page reads those factors against each crop’s thresholds.

What the four marks mean

●

Governs

This factor can limit this system

The factor is read, and it can hold the crop back. If the reading is bad enough, it sets the suitability class on its own. These are the factors that actually decide the answer for this production system.

Example — Soil salinity for open-field tomato. The crop grows in the ground, so a salty soil directly limits it.

○

Does not apply

Measured, but cannot limit this system

The factor was assessed — it is simply irrelevant here. An empty cell would look unfinished; this mark says the question was asked and the answer is that it does not bite for this system.

Example — Soil salinity for protected agriculture. The crop grows in substrate inside a greenhouse and never touches the field soil, so the soil’s salt content cannot reach it.

◖

Qualifies — a bad reading is a good sign

The hazard qualifies the land instead of disqualifying it

A hazard normally disqualifies land. For one activity — land management and restoration — the same hazard qualifies it, because the problem is the very thing the work exists to fix.

Example — Severe wind erosion. For a wheat farm that is a reason to walk away. For a dune-stabilisation programme it is the reason to choose that site — you would not spend the budget stabilising ground that is already stable.

In short: same measurement, opposite verdict. Only the Land Management column carries this mark.

▲

Conditional

Depends on the crop or the setup

The factor may or may not limit this system — it depends which crop is chosen or how the operation is built.

Example — Flood hazard for rain-fed cropping. Usually a constraint, but spate irrigation deliberately farms wadi flood water — so for that setup the same hazard is a resource.

Cells marked with a small blue dot carry a short explanation — hover over the cell to read why that mark was given.

The eight production systems — what each one is, and what actually limits it

Crop Production — split into four production systems

Irrigated Open-Field

Annual crops grown in the ground, watered from a supply

Wheat under centre pivot, open-field tomato, forage. The crop sits directly in the native soil and receives applied water, so it is exposed to everything the ground carries — salt, lime, gypsum, texture, depth — and to everything the climate does. Almost nothing is filtered out. This is the most demanding column in the matrix and the reference case against which the others read as exceptions.

Governs

N/A

Conditional

What decides it: soil chemistry and terrain, because the pivot needs flat ground and the roots are in the native profile.

Orchard & Perennial

Tree and long-lived crops planted once and kept for decades

Date palm, olive, citrus, mango. Reads almost the same factor set as open-field, with two differences that follow from the crop living for thirty years rather than one season: rooting depth matters far more because the tree commits to that profile permanently, and the growing-period window stops mattering — a perennial is not racing to finish inside an annual season.

Governs

N/A

Conditional

What decides it: rooting depth and frost timing — a single badly-timed frost at flowering costs the whole year’s fruit.

Protected Agriculture

Greenhouse and shade-house crops grown in substrate

The crop is lifted out of the ground entirely — it grows in a controlled substrate under a structure. That single fact removes 16 of the 26 factors: all of soil chemistry, most of soil physics, all of drainage. The land underneath is a building site, not a growing medium. What remains is the controlled-environment set: heat, frost, light, water demand, nutrition.

Governs

N/A

Conditional

What decides it: energy cost. Frost and heat set the heating and cooling bill, and that bill decides whether the operation works.

Rain-fed & Supplementary

Crops grown on rainfall, or on seasonal wadi flood water

The mirror image of irrigated cropping on one axis: irrigation demand does not apply, because there is no irrigation. In exchange, the two climate factors that irrigated systems can shrug off — moisture deficit and length of growing period — become the factors that decide everything. Flood hazard also flips: spate systems deliberately farm the flood.

Governs

N/A

Conditional

What decides it: rainfall and the length of the growing window. Nothing can be added to make up a shortfall.

The four remaining sectors — one column each

Livestock & Grazing

Rangeland grazing, fodder production and animal husbandry

The animal does not read the soil — it reads the plants the soil produces, which puts one step between every land factor and the outcome. That is why this column is dominated by conditional marks: whether a soil constraint matters depends entirely on which forage species is grazing on it. What governs directly is erosion, because overgrazing and erosion drive each other, and the climate factors that set how much biomass grows at all.

Governs

N/A

Conditional

What decides it: carrying capacity — how much forage grows per hectare per year, and whether grazing it degrades the site.

Aquaculture

Fish and shrimp production in ponds, tanks or cages

The crop lives in water, not in soil — so almost none of these 26 land factors reach it. The four that do are siting factors: can a pond be built here, will it flood, will sand bury it, is the temperature workable. Its real determinants — water source, salinity of the water body, dissolved oxygen, exchange rate — sit outside this factor set entirely, in the Water module. No marks were invented to fill this column.

Governs

N/A

Conditional

What decides it: the water body, assessed elsewhere. This column answers only “can the facility be built here.”

Agro-industry & Facilities

Processing plants, packhouses, cold stores and logistics

Nothing is grown here, so the land is a foundation, not a growing medium. The soil questions that survive are the ones a structural engineer would ask, not an agronomist: gypsum governs because it dissolves and drops buildings, terrain governs because you need a level pad, and flood and sand encroachment govern because they threaten the asset. Fertility, salinity and climate are irrelevant to a concrete slab.

Governs

N/A

Conditional

What decides it: ground stability and access. The only column where a soil chemical factor matters for engineering rather than agronomy.

Land Management qualifying

Restoration, dune fixation, rangeland rehabilitation

The one column where a hazard qualifies the land rather than disqualifying it. Severe water erosion, wind erosion and sand encroachment do not disqualify a site here — they are the reason to select it. You would not spend a restoration budget on ground that is already stable. Everything else in the column reads normally: the site still needs the soil and climate conditions for the restoration planting to survive.

Governs

Qualifies

Conditional

What decides it: the size of the problem, plus whether restoration planting can actually survive on the site afterwards.

How to read●Governs — can set the class on its own◖Qualifies — the hazard selects the site▲Conditional — depends on the system or setup○Does not apply — assessed, does not biteRead a row across to see how one factor behaves in every production system; read a column down to see which factors a system reads. The same factor can govern one system, not apply to another, and qualify a third.

Code	Diagnostic Factor	Crop Production — four production systems				Livestock & Grazing	Aqua- culture	Agro-industry & Facilities	Land Management
Code	Diagnostic Factor	Irrigated Open-Field	Orchard & Perennial	Protected Agriculture	Rain-fed & Suppl.	Livestock & Grazing	Aqua- culture	Agro-industry & Facilities	Land Management
A · Soil Physical
SQ-A-01	Available Water Capacitys	●	●	○	●	▲	○	○	●
SQ-A-02	Soil Workabilitys	●	▲	○	●	○	○	○	▲
SQ-A-03	Rooting Conditionss	●	●	○	●	▲	○	○	●
SQ-A-04	Surface Sealing & Crustings	●	▲	○	●	▲	○	○	●
SQ-A-05	Soil Textures	●	●	○	●	▲	▲	▲	●
SQ-A-06	Coarse Fragmentss	●	●	○	●	○	○	▲	▲
B · Soil Chemical
SQ-B-01	Salinity (ECe)z	●	●	○	●	▲	○	○	●
SQ-B-02	Sodicity (ESP / SAR)z	●	●	○	●	▲	○	▲	●
SQ-B-04	Toxicity Risk (Boron)n	●	●	▲	○	○	○	○	▲
SQ-B-05	Calcium Carbonaten	●	●	○	●	▲	○	▲	●
SQ-B-06	Gypsum Contentn	●	●	○	●	▲	▲	●	●
SQ-B-07	Soil pHn	●	●	○	●	▲	▲	○	●
C · Water & Drainage
SQ-C-01	Drainage Conditionw	●	●	○	●	▲	▲	▲	●
SQ-C-02	Flood Hazardf	●	●	●	▲	▲	●	●	▲
SQ-C-03	Waterlogging Riskw	●	●	○	●	▲	○	▲	●
D · Topography & Erosion
SQ-D-01	Terrain Workabilityt	●	●	●	●	▲	●	●	●
SQ-D-02	Water Erosion Hazarde	●	●	○	●	●	▲	▲	◖
SQ-D-03	Wind Erosion Hazarde	●	●	▲	●	●	▲	▲	◖
SQ-D-04	Sand Encroachment Hazardd	●	●	●	●	●	●	●	◖
E · Climate
SQ-E-01	Moisture Deficit (Aridity)c	▲	▲	○	●	●	▲	○	●
SQ-E-02	Thermal Suitabilityc	●	●	●	●	▲	●	○	▲
SQ-E-03	Radiation & Solar Energyc	●	●	●	●	○	▲	○	▲
SQ-E-04	Length of Growing Periodc	▲	○	○	●	●	▲	○	▲
SQ-E-05	Frost Riskc	●	●	●	●	▲	▲	○	▲
F · Crop-Specific
SQ-F-01	Irrigation Demand (ETc)i	●	●	●	○	▲	○	○	▲
SQ-F-02	Crop Nutrient Requirementn	●	●	●	●	▲	○	○	▲

🏭

Protected agriculture is mostly ○

It ignores the entire soil-chemical group — the crop is substrate-grown and never contacts field soil — plus most of soil-physical and all of drainage. 16 of 26 factors do not apply. What governs it is thermal, frost, radiation, irrigation demand and crop nutrient requirement: the controlled-environment factors, clustered in Groups E and F. This sparse column is the clearest demonstration on the page that the production system, not the crop, sets the factor list.

🌪

Rain-fed is the mirror image on water

Irrigation demand (SQ-F-01) is ○ — there is no irrigation to demand. But moisture deficit (SQ-E-01) and length of growing period (SQ-E-04) become governing climate factors, where for irrigated systems they are only conditional. Read the two rows together: the same two systems take opposite marks on three consecutive climate and crop factors. Flood hazard is also conditional rather than limiting here, because spate irrigation deliberately uses wadi flood water as the resource.

🐟

Aquaculture responds to almost no land factor

Only 4 of 26 factors govern it, and those are siting factors — terrain for pond construction, flood hazard, sand encroachment, thermal. Its real determinants are water-body qualities that sit outside these 26 land-and-crop factors: water source and volume, salinity of the water body, dissolved oxygen, temperature regime of the water column, and exchange rate. Those are assessed in the Water module and in a sector-specific factor set. No marks have been invented to fill this column.

🌲

Land management reads hazards the other way

The only column carrying ◖ marks. Water erosion, wind erosion and sand encroachment all qualify land for restoration rather than ruling it out. For restoration, the hazard is the reason to act, not a reason to decline. A hectare with severe erosion is a poor candidate for irrigated cropping and an excellent candidate for a stabilisation programme — read from the identical measurement. This mirrors the qualifying marks in the Capability-by-Sector matrix and the conservation exception in the Land Rights & Constraints module.

💧

Irrigation demand is the cleanest split

SQ-F-01 governs every irrigated system and no rain-fed one. Its row shows the split at a glance — three solid marks across the irrigated crop systems, then a single ○ where rain-fed sits. It is the proof that Group F earns its place: a factor that exists only once a crop is named, and that separates production systems more cleanly than any land quality does. Nothing in Groups A–E divides the columns this sharply.

📏

Read the shape before the labels

The four crop-production sub-columns are dense. Protected is sparse but clustered in E and F. Aquaculture is nearly empty. Land management is dense with three qualifying marks in Group D. Someone scanning this page should see those four shapes before reading a single factor name — the distribution of marks is itself the finding, and it is why the sub-columns could not be collapsed into one crop-production column.

The same land data, two different factor sets

A hectare that is capable and routed to crop production is assessed against a different set of factors depending on how the crop would be grown. Not different data — the same measurements, read through a different filter.

Open-field date palm

Assessed on 24 governing factors — soil salinity, carbonate, gypsum, texture, rooting depth, drainage, terrain, erosion, all four climate factors, frost, and irrigation demand.

Protected date palm

Assessed on 8 governing factors — thermal, frost, radiation, flood hazard, terrain for structure siting, sand encroachment, irrigation demand, crop nutrient requirement. The soil chemistry is not read at all.

This is why one hectare can be S2 for open-field date palm and S1 for the same crop under protected conditions — not because the land changed, but because a limiting factor in one system is not read in the other. If the S2 was driven by soil salinity, protection removes that constraint entirely.

What this page does not do. It carries no threshold values — those are per-crop and live in the Crop-Specific stage. A cell says whether a factor applies, never how much is too much. The moment a cell holds a number, the production systems stop being comparable and the routing logic is lost. It does not produce a suitability class, and it does not re-derive any factor — it reads the factor set defined on Page 1 and marks applicability.

Derivation status. Cells marked ● or ○ are derived from the crop requirement tables: a factor governs a production system where the crops grown that way carry a threshold table for it. Cells marked ▲ are conditional — the ALUES database currently has complete threshold extraction for one crop only, so where the crop data is incomplete the cell is marked conditional rather than guessed as governs or does-not-apply. The livestock and aquaculture columns carry the highest proportion of conditional marks, because both cover several distinct forms of production under one heading.

Irrigated Open-Field

Annual crops grown in the ground, watered from a managed supply.

Minimum viable area50 ha for centre pivot · smaller for surface and drip layouts

Distinguishing featureThe reference case. Every factor is read, and the crop threshold library applies in full.

What is being evaluated

The crop species. All 26 factors are read against that crop’s own tolerances.

Irrigation method — how it changes which factors bite

Drip

Water delivered to the root zone. Foliage never wetted.

Chloride tolerance rises — SQ-B-04 and water chloride are read against the soil pathway only, not foliar burn. Slope tolerance is highest of the four methods: drip works on ground a pivot cannot cross. Highest capital cost per hectare, lowest water demand.

Sprinkler

Overhead application. Foliage is wetted at every irrigation.

Chloride and sodium become foliar risks, not just root-zone risks. FAO-29 applies stricter limits under sprinkler than surface application for the same water. Wind speed matters for distribution uniformity — a factor no current element captures.

Centre pivot

Self-propelled circular system covering 50–125 ha per unit.

Imposes a minimum area and a shape. SQ-D-01 terrain becomes binding well before it would for drip — the tower must traverse the whole circle. Sub-50 ha blocks are not viable regardless of every other factor.

Surface / flood

Water moved across the field by gravity.

Requires near-level ground: SQ-D-01 is the governing factor. Demands high water volume, so SQ-F-01 irrigation demand and the water module’s volume parameters bind hardest. Salinity accumulates faster without a controlled leaching fraction.

All 26 factors — and how delivery method changes each

System column●Governs — can set the class on its own▲Conditional — depends on the system or setup○Does not applyMethod columns↑Amplified — binds harder under this method●Standard — behaves as it does for the system generally↓Reduced — the method mitigates this factor◖Inverted — the method turns the factor into a capabilityRead a row across: the system column is the base mark, the four method columns show how that behaviour shifts with delivery. The method marks describe the direction of effect — whether a factor bites harder or less hard under each delivery method.

Code	Diagnostic factor	This system	Shift by delivery method
Code	Diagnostic factor	This system	Drip	Sprinkler	Centre pivot	Surface / flood
A · Soil Physical
SQ-A-01	Available Water Capacitysⓘ	●	↓	●	●	↑
Surface applies large volumes infrequently, so the soil must store between irrigations. Drip refills the root zone daily and compensates for low holding capacity.
SQ-A-02	Soil Workabilitysⓘ	●	●	●	●	↑
Surface irrigation requires land levelling before the first crop. Workability governs the cost of that operation; the other three methods do not need it.
SQ-A-03	Rooting Conditionss	●	●	●	●	●
SQ-A-04	Surface Sealing & Crustingsⓘ	●	↓	↑	↑	↑
Sprinkler and pivot droplets strike bare soil and drive crust formation. Drip never wets the surface between emitters.
SQ-A-05	Soil Texturesⓘ	●	↓	●	●	↑
Texture sets the infiltration rate, which determines furrow length and basin size in surface systems. Under drip the emitter rate is set independently of the soil.
SQ-A-06	Coarse Fragmentssⓘ	●	↓	●	↑	↑
Tower wheels and levelling equipment both suffer on stony ground. Drip lines are laid over it.
B · Soil Chemical
SQ-B-01	Salinity (ECe)zⓘ	●	●	↑	↑	↑
Sprinkler and pivot wet the foliage, adding a leaf-burn pathway to the root-zone effect. Surface accumulates salt fastest without a controlled leaching fraction. FAO-29 sets stricter limits for overhead application.
SQ-B-02	Sodicity (ESP / SAR)zⓘ	●	↓	●	●	↑
Sodium collapses infiltration. That is fatal to surface irrigation, which depends on water moving across and into the profile; drip delivers under pressure to a point.
SQ-B-04	Toxicity Risk (Boron)nⓘ	●	●	●	●	●
Boron is taken up through the root regardless of delivery method.
SQ-B-05	Calcium Carbonaten	●	●	●	●	●
SQ-B-06	Gypsum Contentnⓘ	●	●	●	●	↑
Gypsum dissolves and can destabilise levelled basins and channels.
SQ-B-07	Soil pHn	●	●	●	●	●
C · Water & Drainage
SQ-C-01	Drainage Conditionwⓘ	●	●	●	●	↑
Surface irrigation applies large volumes at once. Without free drainage the root zone stays saturated far longer than under any pressurised method.
SQ-C-02	Flood Hazardf	●	●	●	●	●
SQ-C-03	Waterlogging Riskwⓘ	●	↓	●	●	↑
Same reason as drainage — application volume per event drives the risk.
D · Topography & Erosion
SQ-D-01	Terrain Workabilitytⓘ	●	↓	●	↑	↑
The primary differentiator. Drip works on ground no other method can cross. Pivot towers must traverse the whole circle. Surface needs near-level ground and governs hardest of the four.
SQ-D-02	Water Erosion Hazardeⓘ	●	↓	↑	↑	↑
Overhead droplet energy and surface flow both detach soil. Drip does neither.
SQ-D-03	Wind Erosion Hazardeⓘ	●	●	↑	↑	●
Wind distorts sprinkler and pivot distribution uniformity as well as eroding soil — a compounding effect no current element captures.
SQ-D-04	Sand Encroachment Hazarddⓘ	●	↑	●	↑	●
Emitters clog with wind-blown fines; pivot towers suffer mechanical damage from drifting sand.
E · Climate
SQ-E-01	Moisture Deficit (Aridity)c	▲	●	●	●	●
SQ-E-02	Thermal Suitabilityc	●	●	●	●	●
SQ-E-03	Radiation & Solar Energyc	●	●	●	●	●
SQ-E-04	Length of Growing Period (LGP)c	▲	●	●	●	●
SQ-E-05	Frost Riskcⓘ	●	●	◖	◖	●
Inverted. Sprinkler and pivot systems are deliberately run during radiation frost — the latent heat released as water freezes on the plant holds tissue near 0 °C. Frost risk becomes a capability the method provides, not a limitation.
F · Crop-Specific
SQ-F-01	Irrigation Demand (ETc)iⓘ	●	↓	●	●	↑
Application efficiency differs sharply: drip is the highest of the four, surface the lowest. The same crop demand becomes a different abstraction requirement.
SQ-F-02	Crop Nutrient Requirementnⓘ	●	↓	●	●	↑
Fertigation through drip places nutrients in the wetted zone. Surface systems broadcast, and losses on a calcareous soil are higher.

24 factors govern this system and 2 are conditional — shown in the system column. Of the 26, eighteen behave differently depending on how water is delivered; those rows carry ⓘ and open an explanation on click. The remaining eight are read identically under all four methods.

Orchard & Perennial

Tree and long-lived crops planted once and kept for decades.

Minimum viable area10 ha — harvest crews, grading and cold-chain handling do not amortise below this

Distinguishing featureThe distinguishing question is time. A 30-year planting must be matched against a water supply horizon, not just current availability.

What is being evaluated

The tree or vine species, assessed over its full productive life rather than one season.

Why the water finding binds harder here

A W2y source with a 28-year remaining horizon is adequate for an annual crop and marginal for a date palm planting that reaches full bearing at year 8 and yields for decades. The suitability class does not capture this — the water state must be read alongside it.

Rooting depth carries more weight

SQ-A-03 governs more strongly than for annuals. A shallow profile that a wheat crop tolerates for one season constrains a tree permanently, and the planting cannot be relocated.

How to read●Governs — can set the class on its own◖Qualifies — the hazard selects the site▲Conditional — depends on the system or setup○Does not apply — assessed, does not biteEvery factor is listed under exactly one heading below. The four headings together account for all 26 — a factor absent from one list appears in another.

●Factors that govern this system22 of 26

SQ-A-01Available Water Capacity●

SQ-A-03Rooting Conditions●

SQ-A-05Soil Texture●

SQ-A-06Coarse Fragments●

SQ-B-01Salinity (ECe)●

SQ-B-02Sodicity (ESP / SAR)●

SQ-B-04Toxicity Risk (Boron)●

SQ-B-05Calcium Carbonate●

SQ-B-06Gypsum Content●

SQ-B-07Soil pH●

SQ-C-01Drainage Condition●

SQ-C-02Flood Hazard●

SQ-C-03Waterlogging Risk●

SQ-D-01Terrain Workability●

SQ-D-02Water Erosion Hazard●

SQ-D-03Wind Erosion Hazard●

SQ-D-04Sand Encroachment Hazard●

SQ-E-02Thermal Suitability●

SQ-E-03Radiation & Solar Energy●

SQ-E-05Frost Risk●

SQ-F-01Irrigation Demand (ETc)●

SQ-F-02Crop Nutrient Requirement●

▲Conditional — depends on the crop or the setup3 of 26

SQ-A-02Soil Workability▲

SQ-A-04Surface Sealing & Crusting▲

SQ-E-01Moisture Deficit (Aridity)▲

○Does not apply1 of 26

SQ-E-04Length of Growing Period (LGP)○

Assessed, and found not to bite. An empty cell would look unfinished; this states the question was asked.

Protected Agriculture

Greenhouse and shade-house crops grown in substrate.

Minimum viable area2 ha — high value per square metre makes small blocks commercially viable

Distinguishing feature16 of the 26 factors do not apply. Substrate cultivation bypasses the field soil entirely, which is why this system can develop land the open-field assessment rejects.

What is being evaluated

The crop species, but read against a controlled root environment rather than the field soil.

What the structure replaces

Soil physical and chemical factors are removed from the assessment because the crop never contacts the field soil. Salinity, sodicity, texture, carbonate, gypsum, pH, rooting depth and coarse fragments are all N/A — not favourable, simply not read.

What still governs

Terrain for construction, water quality for the irrigation solution, radiation, and the thermal envelope the structure must manage. Water quality governs more strictly than open field — there is no soil buffer to absorb salinity.

The consequence for land inventory

A hectare rated poor for open-field cropping on soil chemistry may be fully suitable for protected agriculture. This is the clearest case in the study of a system rescuing land another system rejects.

How to read●Governs — can set the class on its own◖Qualifies — the hazard selects the site▲Conditional — depends on the system or setup○Does not apply — assessed, does not biteEvery factor is listed under exactly one heading below. The four headings together account for all 26 — a factor absent from one list appears in another.

●Factors that govern this system8 of 26

SQ-C-02Flood Hazard●

SQ-D-01Terrain Workability●

SQ-D-04Sand Encroachment Hazard●

SQ-E-02Thermal Suitability●

SQ-E-03Radiation & Solar Energy●

SQ-E-05Frost Risk●

SQ-F-01Irrigation Demand (ETc)●

SQ-F-02Crop Nutrient Requirement●

▲Conditional — depends on the crop or the setup2 of 26

SQ-B-04Toxicity Risk (Boron)▲

SQ-D-03Wind Erosion Hazard▲

○Does not apply16 of 26

SQ-A-01Available Water Capacity○

SQ-A-02Soil Workability○

SQ-A-03Rooting Conditions○

SQ-A-04Surface Sealing & Crusting○

SQ-A-05Soil Texture○

SQ-A-06Coarse Fragments○

SQ-B-01Salinity (ECe)○

SQ-B-02Sodicity (ESP / SAR)○

SQ-B-05Calcium Carbonate○

SQ-B-06Gypsum Content○

SQ-B-07Soil pH○

SQ-C-01Drainage Condition○

SQ-C-03Waterlogging Risk○

SQ-D-02Water Erosion Hazard○

SQ-E-01Moisture Deficit (Aridity)○

SQ-E-04Length of Growing Period (LGP)○

Assessed, and found not to bite. An empty cell would look unfinished; this states the question was asked.

Rain-fed & Supplementary

Crops grown on rainfall, or on seasonal wadi flood water.

Minimum viable area20 ha — area averages year-to-year rainfall variance into a predictable return

Distinguishing featureViable only in the southwestern highlands and on wadi systems. Across most of the Kingdom rainfall alone cannot support a crop cycle.

What is being evaluated

The crop species, read against rainfall and stored soil moisture rather than a managed supply.

Flood hazard inverts here

SQ-C-02 is marked Conditional rather than Governs because spate irrigation deliberately farms wadi flood water. The same hazard that disqualifies an orchard is the water source for a spate system. The mark depends on whether the operation is designed to capture flow or to exclude it.

Moisture deficit is the binding factor

SQ-E-01 governs almost everywhere. This is the system where the version 10.1 change matters most — moisture deficit is now crop-keyed, so the threshold is the named crop’s water requirement rather than a general aridity cut.

How to read●Governs — can set the class on its own◖Qualifies — the hazard selects the site▲Conditional — depends on the system or setup○Does not apply — assessed, does not biteEvery factor is listed under exactly one heading below. The four headings together account for all 26 — a factor absent from one list appears in another.

●Factors that govern this system23 of 26

SQ-A-01Available Water Capacity●

SQ-A-02Soil Workability●

SQ-A-03Rooting Conditions●

SQ-A-04Surface Sealing & Crusting●

SQ-A-05Soil Texture●

SQ-A-06Coarse Fragments●

SQ-B-01Salinity (ECe)●

SQ-B-02Sodicity (ESP / SAR)●

SQ-B-05Calcium Carbonate●

SQ-B-06Gypsum Content●

SQ-B-07Soil pH●

SQ-C-01Drainage Condition●

SQ-C-03Waterlogging Risk●

SQ-D-01Terrain Workability●

SQ-D-02Water Erosion Hazard●

SQ-D-03Wind Erosion Hazard●

SQ-D-04Sand Encroachment Hazard●

SQ-E-01Moisture Deficit (Aridity)●

SQ-E-02Thermal Suitability●

SQ-E-03Radiation & Solar Energy●

SQ-E-04Length of Growing Period (LGP)●

SQ-E-05Frost Risk●

SQ-F-02Crop Nutrient Requirement●

▲Conditional — depends on the crop or the setup1 of 26

SQ-C-02Flood Hazard▲

○Does not apply2 of 26

SQ-B-04Toxicity Risk (Boron)○

SQ-F-01Irrigation Demand (ETc)○

Assessed, and found not to bite. An empty cell would look unfinished; this states the question was asked.

This is the crop library. The Factors tab defines what is measured; the By Industry tab decides which factors a production system reads. This tab holds the other half of the equation — each crop’s own tolerances, the ruler that a measurement is read against. Select any crop to see its full ecological requirement record.

Status: All 63 crops now carry requirement data. 56 crops hold complete numeric S1–N thresholds — 1,268 records across 91 parameters, extracted from ALUES 0.2.1 and source-validated. 7 Saudi-priority crops hold full FAO ECOCROP ecological profiles. No crop is yet operational: production-system-specific thresholds still require Saudi calibration and expert approval before national release.

Select a crop to see its full ecological requirement record — temperature, rainfall, soil, light and production-system detail.

Aquaculture

Fish and shrimp production in ponds, tanks or cages.

Factor routing4 govern · 12 N/A · 10 conditional

What is being evaluated

Not a crop. Two things are evaluated: the site’s physical ability to hold water, and the water quality available for the species. The species set follows the water available — shrimp and marine finfish on the coast, tolerant freshwater species inland.

●Factors that apply to every kind of aquaculture4

SQ-C-02Flood HazardPonds and dikes have to survive a flood. On a wadi it can also be the fill source.

SQ-D-01Terrain WorkabilityPonds need flat ground. A slope means far more earth to move.

SQ-D-04Sand Encroachment HazardDrifting sand fills ponds and blocks intakes.

SQ-E-02Thermal SuitabilityWater temperature drives growth rate and decides which species can be kept.

▲Factors that apply to some kinds only10

SQ-A-05Soil TextureClay holds water in and makes strong banks. Sand does neither, so a sand site needs a liner.

SQ-B-06Gypsum ContentGypsum dissolves and can undermine dikes and pond floors.

SQ-B-07Soil pHPond soil pH affects water chemistry and how well natural food grows.

SQ-C-01Drainage ConditionA pond with no liner needs ground that keeps water in. Ground that drains well lets the pond empty into the subsoil.

SQ-D-02Water Erosion HazardRunoff can breach dikes and silt up ponds.

SQ-D-03Wind Erosion HazardWind drives evaporation and blows sand into the water.

SQ-E-01Moisture Deficit (Aridity)Evaporation from an open pond is a permanent loss that has to be replaced.

SQ-E-03Radiation & Solar EnergySunlight grows the plankton in the pond. This matters most where the fish feed on it rather than on pellets.

SQ-E-04Length of Growing Period (LGP)Sets how many months a year the water is warm enough to grow stock.

SQ-E-05Frost RiskCold water stops growth and can kill warm-water species.

These bite for earthen ponds, where the ground itself holds the water. They do not bite for lined ponds, tanks or cages, where it does not.

+Elements to add for aquaculture3

SQ-D-05Coastal positionDistance to the shore and height above sea level, together. Decides whether seawater can reach the site, and whether ponds fill and drain by gravity or need pumps running all the time.

WP-A-01 · WOMarine water sourceA seventh source code for seawater. The six existing codes are all inland. Seawater does not run out, does not fall in level and is not allocated from a basin, so it cannot be recorded as any of them.

SQ-D-06Tide rangeHeight difference between high and low water. Sets how deep the pond floor must sit and whether it can be drained without pumping.

The three ways aquaculture is done

How it works

Earthen ponds are dug into the ground and banked with the excavated soil. They fill from a well, canal or wadi, and are drained to harvest.

A pond is a small living system. It is not simply a tank of water. Nutrients in the water and the bottom soil grow microscopic plants; those feed tiny animals and insect larvae; the fish eat those. So the soil is not just a container — it is the base of the food chain. This is why a pond can be fertilised: the fertiliser grows the plankton, and the plankton feeds the fish.

What a pond actually is

A rectangular basin excavated into the ground, typically 0.5–2 ha and 1–1.5 m deep. The soil dug out is used to build the banks, so the excavation and the wall come from the same operation. It is filled from a well, canal or wadi and drained completely at harvest.

The basinThe hole itself. Its floor is graded to fall gently toward the outlet so the pond can be emptied by gravity.

The dikesThe raised banks holding the water. Built from the excavated soil, compacted in layers. Wide enough on top for a vehicle on at least one side.

The inletPipe or channel bringing water in, usually with a screen to keep wild fish and debris out.

The outlet / monkA gated structure at the low point. Lets the operator drop the level, drain fully at harvest, and skim water from a chosen depth.

The pond bottomNot just a floor. Nutrients in the soil grow the plankton the fish feed on, so the bottom is a working part of the farm.

What "lined" means — Lined means an impermeable barrier is installed between the water and the soil, so the soil is no longer what holds the water in. The hole, the dikes and the outlet are unchanged — only the containment moves from the ground to a manufactured layer. Common forms are a welded HDPE sheet, a bentonite clay blanket that swells and self-seals, or imported clay compacted in place. Partial lining is common — floor lined and dikes left earthen, or the reverse — which is why the sub-system does not split cleanly in two.

If the pond is not lined, the soil is what holds the water in. If it is lined, the soil only gives the pond its shape.

Why does the soil matter if you can line the pond?

A pond can be lined. If it is, the liner holds the water in and the soil no longer has to.

But clay leaks about as little as a liner does. Build on clay and the pond holds water on its own, with nothing added. Build on sand and it does not — sand leaks roughly a hundred times faster, so a liner has to go in before the pond can be used at all.

How the pond is builtWater lost through the bottom, m³/ha/yr

Unlined sand92,700–927,000

Unlined clay927–9,271

Bentonite liner927–4,636

HDPE sheet0–93

Concrete0–93

Compare it with evaporation, which takes about 22,500 m³/ha/yr in the Kingdom. On clay, what leaks through the bottom is about a quarter of that — small beside it. On sand it is 22 times more than evaporation. No water supply can keep up with that.

A liner does not remove the soil from the picture. The banks are still built from the soil dug out, and they have to hold their own weight and the water behind them. The ground still has to be firm enough to dig and shape. A liner changes none of that.

And a liner covers the pond bottom. That is where the natural food grows, so a lined pond has to be fed more to reach the same yield.

Scale and production

Typical pond0.5–2 ha each, water 1–1.5 m deep

Water — flow-through5 l/sec/ha ≈ 157,000 m³/ha/yr (FAO)

Water — recirculating≈ 21,000–34,000 m³/ha/yr in KSA conditions

Initial fill≈ 12,500 m³/ha at 1.25 m depth

Yield — natural food onlyUnder 1 t/ha/yr

Yield — water fertilised1–2 t/ha/yr

Yield — fertilised + fed3–10 t/ha/yr

The fertiliser goes into the water, not onto a crop. It blooms the plankton that the fish graze on — the three yields above are three different food sources, not three feeding rates. Fertilising roughly doubles what natural productivity alone supports; adding manufactured pellets lifts it again by several times.

Intensive shrimp3–6 t/ha/yr at 10–30 shrimp per m²

Read the two water figures carefully. They are not alternatives for the same design. The flow-through figure assumes water is discharged after a single pass; the recirculating figure assumes it is treated and returned, so only evaporation and seepage are replaced. Which one applies is an engineering choice, and it changes the abstraction licence by a factor of six.

What limits it

The soil must hold water. A pond on sandy ground leaks faster than it can be filled. That single requirement rules out most of the Kingdom’s open desert.

How much water a pond farm uses depends on how the pond is designed, not on how many fish are in it. The FAO figure of 5 l/sec/ha is for a flow-through pond, where water runs through continuously to carry waste away. That is 157,000 m³/ha/yr — about 12 complete pond exchanges a year. A pond that recirculates through a settling basin or biofilter does not need that: it only replaces what it physically loses.

In the Kingdom what it loses is mostly evaporation. At roughly 2,000–2,500 mm a year from an open surface, plus modest seepage through clay, a recirculating pond still needs 21,000–34,000 m³/ha/yr — six times less than flow-through, but far from nothing. Evaporation alone is comparable to the irrigation demand of a field crop on the same hectare.

Ground must be near level. On a slope far more earth has to be moved to get a flat basin, and draining the pond by gravity only works if the bottom sits above the outlet.

Environmental impact to watch

EffluentPond water carries feed residue, fish waste and any fertiliser added to bloom the plankton. Discharged untreated it enriches whatever receives it — the same nutrients that grow food inside the pond cause algal blooms outside it.

Soil salinisationRepeated filling and evaporation concentrates salt in and around the pond. Land beside a pond can degrade over years.

Groundwater drawIn the Kingdom the fill and makeup water is pumped. Even a recirculating pond abstracts continuously to replace evaporation, competing with irrigation on the same aquifer. A flow-through design competes six times harder.

SludgeOrganic matter accumulates on the bottom and must be removed between cycles. Where it is put matters.

How it works

Fish are held in tanks inside a building. The same water circulates continuously through filters that strip out waste and add oxygen, so only a small fraction is replaced each day. The system is engineered from end to end — nothing depends on the site’s natural conditions.

What a tank / RAS system actually is

Fish are held in tanks — usually circular, in concrete, fibreglass or coated steel — inside a building. The same water circulates continuously through a treatment loop and returns to the tank, so only a small fraction is replaced each day. RAS stands for recirculating aquaculture system.

The tanksCircular is standard: the rotating flow sweeps solids to a central drain and keeps the fish swimming evenly.

Mechanical filterScreens or a drum filter removing solid waste and uneaten feed before it breaks down.

Biological filterThe heart of the system. Bacteria growing on a high-surface-area medium convert ammonia from the fish into nitrate, which is far less toxic.

OxygenationFish at high density consume oxygen faster than the water can absorb it from air. Pure oxygen or intensive aeration is injected continuously.

DegassingStrips out carbon dioxide the fish exhale, which would otherwise acidify the water.

DisinfectionUV or ozone, controlling pathogens in a closed loop where disease would otherwise spread through the whole stock.

Is it lined? — There is nothing to line. The tank is a manufactured vessel standing on a prepared floor, and the ground beneath it carries load rather than water. The site question becomes bearing capacity, power supply and effluent disposal — not soil texture or drainage.

The site only needs to give a firm floor, an electricity supply and a drain. Nothing about the soil or climate affects the fish.

Scale and production

Water reuseLess than a tenth of what a pond of the same output would use

Stocking densityAround 70–120 kg per cubic metre

FootprintMuch less land than a pond farm needs to produce the same amount

SitingIt can be built near the market, because it does not need to be near a water source

ControlTemperature and water quality are held steady all year

What limits it

Everything has to be built and nothing comes from the site. Tanks, filters, pumps and oxygen supply all have to be installed before a single fish is stocked. This is the main reason RAS has not spread widely outside developed markets.

Power is continuous and non-negotiable. Pumps, filters and oxygenation run without pause. An interruption of hours can kill the entire stock.

It needs trained operators. The biological filter is a living system. Mismanage it and water quality collapses quickly, with no pond volume to buffer the error.

Environmental impact to watch

EnergyThe burden shifts from water to electricity. On a grid running on fossil fuel, a RAS farm carries a real carbon footprint.

Concentrated wasteVery little water leaves, but what does is highly concentrated. It has to be treated before it leaves the site. It cannot simply be discharged.

Sludge disposalSolids removed by the filters accumulate as a continuous waste stream requiring a disposal route.

BrineWhere the source is brackish or the system uses saline water, reject brine needs somewhere to go — the same problem desalination faces.

How it works

Net cages float in open coastal water. Fish are fed inside them and waste passes straight through the mesh into the sea, which dilutes it. Nothing is built on land except the shore base.

What a marine cage actually is

A net bag suspended from a floating collar in open coastal water. Fish are fed inside it, and waste passes through the mesh into the sea, which disperses it. Nothing is built on land except the shore base.

The collarA floating ring, commonly HDPE pipe, holding the cage open at the surface and providing a walkway.

The netThe containment itself. Sized by species and stocking, weighted at the base to hold shape against current.

The mooringAnchors and lines holding the cage on station. The heaviest engineering in the system, and what fails first in a storm.

Predator netAn outer net keeping seals, sharks and birds off the stock net.

Feed systemBarge or shore-fed pipework. Feeding is the main daily operation.

The shore baseJetty, feed store, handling and cold chain. This is the only part that occupies land.

Does lining apply? — The concept does not apply. The sea is the container. The site question is depth beneath the cage, current speed, shelter from storm, and what the seabed can absorb — none of which the hectare grid assesses, because the grid stops at the coast.

A cage site is judged by the water it sits in, not by any land. This study measures land only, so it cannot score cage sites.

Scale and production

DensityRoughly 100–300 kg per cubic metre of cage

Yield by cage areaCan reach 100 t/ha of cage surface

Yield by water bodyAbout 1 t/ha once the surrounding water that dilutes the waste is counted in

Site needsShelter from storms, sufficient depth beneath the cage, and current to carry waste away

Land neededOnly a base on shore, holding the feed store, jetty and handling area

What limits it

This is not a land question. The hectare grid does not reach the sea, so no cell in this study can be assessed for cage siting. It is listed here for completeness of the sector.

The site must be sheltered but not still. Too exposed and cages are lost to storms; too enclosed and waste accumulates beneath them.

Coastal space is contested. Shipping, tourism, ports and conservation designations all compete for the same water.

Environmental impact to watch

Seabed beneath the cagesUneaten feed and faeces settle directly below. Without adequate current and depth the sediment goes anoxic.

EscapesFarmed fish that escape can interbreed with or displace wild populations.

Disease and parasitesDense stock in open water can transfer disease to wild fish passing through.

Chemical useTreatments applied in the cage disperse into the surrounding water, unfiltered.

How it works

Ponds built on flat coastal land, filled with seawater pumped in from the sea. The water is cleaned on the way out and returned. This is how nearly all Saudi aquaculture is done. It looks like a pond farm and behaves like one, but it draws on the sea instead of an aquifer.

What a coastal farm actually is

A chain of ponds running from the sea and back to it: take water in, settle it, grow in it, clean it, return it.

The intakePumps or a canal bringing seawater in from beyond the surf line. On the biggest farms this is the largest single piece of engineering.

Reservoir pondsSeawater is held and settled before it reaches the fish, so sand and silt drop out first.

Grow-out pondsWhere the shrimp or fish are kept. Often round with a drain in the middle, so aerators push the waste to the centre.

Treatment pondsWater leaving the grow-out ponds is cleaned in further ponds before it goes back to the sea. On some farms this takes as much land as the production itself.

The outfallWhere treated water returns to the sea. Placed well away from the intake so the farm does not draw back its own discharge.

The sea provides the water and also receives it back. A site needs a good place to take water in and a separate place to return it.

Scale and production

Pond size1–10 ha each, often round with a centre drain

Water sourceSeawater at full strength. No fresh water is used at all

Intake scaleUp to 90 m³/second on the largest farms

Land for cleaningThe cleaning ponds can take as much land as the production ponds, or more

Shrimp yield15–20 t/ha/yr reported on Red Sea farms

SpeciesMostly shrimp, and some barramundi

What limits it

It has to be close to the sea and low down. Every metre of height and every kilometre inland adds pumping that never stops.

Flat land near the shore is limited. The coastal strip is narrow, and ports, tourism and conservation want the same ground.

Both ends have to work. A site needs somewhere to draw clean seawater from and somewhere to return it, far enough apart that the farm does not take back its own discharge.

Environmental impact to watch

Return waterEverything taken from the sea goes back to it. Cleaning it first is the whole reason treatment ponds exist.

Mangrove and shorelineCoastal habitat is easily lost to pond construction. Once cleared it does not come back quickly.

Intake and outfall placingPut them too close together and the farm recycles its own waste.

Salt in the groundPonds of seawater sitting on land will salt the soil around and beneath them.

Livestock & Grazing

Rangeland grazing, fodder production and animal husbandry.

Factor routing5 govern · 4 N/A · 17 conditional

What is being evaluated

Not a crop, and not the animal. What is assessed is the forage resource — what the land can produce and sustain — plus stock water and heat stress.

●Factors that apply to every kind of livestock production5

SQ-D-02Water Erosion HazardOvergrazing strips cover and the soil washes away. The land loses what feeds the animals.

SQ-D-03Wind Erosion HazardBare rangeland blows away. Wind erosion is what turns grazing land into desert.

SQ-D-04Sand Encroachment HazardMoving sand buries the plants animals feed on.

SQ-E-01Moisture Deficit (Aridity)Rainfall decides how much grass and browse grows, and so how many animals the land can carry.

SQ-E-04Length of Growing Period (LGP)Sets how many months a year there is anything green to eat.

▲Factors that apply to some kinds only17

SQ-A-01Available Water CapacityThis matters where fodder is grown. Native rangeland plants already suit the soil they grow in.

SQ-A-03Rooting ConditionsThis matters for sown fodder. Native shrubs root much deeper than any crop does.

SQ-A-04Surface Sealing & CrustingA crust stops seedlings coming up when rangeland is reseeded.

SQ-A-05Soil TextureDecides what grows naturally and whether fodder can be established.

SQ-B-01Salinity (ECe)Salt limits what fodder crops will grow. Many native range plants tolerate much more of it.

SQ-B-02Sodicity (ESP / SAR)This affects sown fodder. Native plants are generally less affected by it.

SQ-B-05Calcium CarbonateIt locks up nutrients where fodder is grown. It has less effect on natural grazing.

SQ-B-06Gypsum ContentIt affects sown fodder more than it affects native plants already growing.

SQ-B-07Soil pHDecides which fodder species will establish.

SQ-C-01Drainage ConditionThis matters where fodder is irrigated. Rangeland rarely holds enough water for it to be a problem.

SQ-C-02Flood HazardFlooding damages fodder fields and fencing. On rangeland, seasonal flood water often grows the best grazing.

SQ-C-03Waterlogging RiskThis affects fodder fields. It rarely happens on dry rangeland.

SQ-D-01Terrain WorkabilityGrowing fodder needs flat ground for machinery. Animals can graze slopes that a tractor cannot cross.

SQ-E-02Thermal SuitabilityHeat limits fodder growth, and also stresses the animals themselves.

SQ-E-05Frost RiskFrost stops fodder growth and can kill young stock.

SQ-F-01Irrigation Demand (ETc)This only applies where fodder is irrigated. Natural grazing is not irrigated.

SQ-F-02Crop Nutrient RequirementThis applies to fodder crops. Native range plants already grow in poor soil.

Almost all of these bite for grown fodder and not for natural grazing. Fodder is a crop and reads the crop thresholds; rangeland is native vegetation already suited to the ground it grows on.

+Elements to add for livestock4

SQ-G-01Carrying capacityHow many animals a hectare can feed without degrading. The core measure for grazing, and unlike every other factor it is a productivity estimate rather than a threshold comparison.

SQ-G-02Stock water requirementWater for the animals to drink. Far smaller than irrigation but never zero, and it decides how far stock can range from a water point.

SQ-G-03Heat stress on animalsTemperature and humidity as the animal experiences them. All current thermal factors are read for plant growth. None asks whether the animal can tolerate the conditions.

SQ-G-04Distance to water pointHow far an animal must walk to drink. Grazing concentrates near water and degrades there first. The spacing of water points shapes the whole grazing pattern.

The three ways livestock is kept

How it works

Animals graze native plants across open country. Nothing is planted and nothing is irrigated. The herd moves to follow what has grown after rain.

Scale and inputs

Minimum areaAbout 1,000 ha — arid rangeland carries too few animals to manage smaller

StockingFew animals per hectare, and the number changes with the season and the rainfall

InputsNothing is added to the land itself

AnimalsCamels, sheep and goats

What the land givesGrass and shrub leaves that are already growing there

What limits it

Rain decides everything. A dry year means less feed, and the herd has to move or shrink.

Water points control where animals go. They gather near water and the ground there wears out first, however much grazing is left further out.

Recovery is slow. Once native cover is lost in an arid climate it does not come back in a season.

Environmental impact to watch

OvergrazingMore animals than the land can feed strips the cover and the soil goes with it.

Damage around waterThe ground near every water point is the first to be worn bare.

Loss of good speciesAnimals eat the palatable plants first, leaving the ones nothing wants.

Wind erosionOnce the cover is gone the surface starts to move.

How it works

Feed crops such as alfalfa and Rhodes grass are grown under irrigation and cut for the animals. This is crop farming. The animals are fed the cut plants, and may be kept far from the field where it grew.

Scale and inputs

What it really isIt is an irrigated crop, so it is assessed using the crop thresholds

SpeciesAlfalfa and Rhodes grass are the main ones

Water useHigh. Alfalfa is among the thirstiest crops grown in the Kingdom

Where it fitsIt is assessed in the crop section, as irrigated open-field cropping

YieldThe plants are cut and carried to the animals several times a year

What limits it

Water is the whole constraint. Fodder is grown to feed animals, but it competes directly with food crops for the same water.

It belongs with the crops. Rhodes grass already sits in the 63-crop library, so this is assessed as a crop and routed there.

Environmental impact to watch

Water useThe main concern. Fodder can use more water per hectare than the food crops beside it.

Aquifer drawWhere it runs on groundwater it draws on the same source as everything else.

Salt build-upHeavy irrigation without proper leaching concentrates salt in the soil.

How it works

Animals are kept in pens or sheds and fed on brought-in feed. The land underneath does almost nothing except hold the buildings.

Scale and inputs

What the land givesFirm level ground, and somewhere for waste water to drain

FeedAll feed is bought in, and much of it is imported

WaterWater is needed for the animals to drink and for washing the pens

AreaA small area compared with any grazing system

Where it sitsThe site is chosen for its road access and closeness to market

What limits it

Soil quality barely matters. What decides the site is water supply, road access and somewhere to put the waste.

It is a siting question. The land assessment can say the ground is firm and level. Everything else that matters sits outside this study.

Environmental impact to watch

ManureConcentrated in one place. Where it goes is the main environmental question.

Water pollutionRunoff from pens carries nutrients and bacteria into the ground and any watercourse.

Smell and fliesReal constraints on how close such a site can be to housing.

Imported feedThe environmental effect of growing the feed happens wherever it was grown. It does not show up at this site.

Agro-industry & Facilities

Processing plants, packhouses, cold stores and logistics.

Factor routing4 govern · 14 N/A · 8 conditional

What is being evaluated

Not a biological subject at all. What is assessed is the land’s ability to carry a structure and the site’s access to production and market.

●Factors that apply to every kind of facility4

SQ-B-06Gypsum ContentGypsum dissolves under a building and the ground settles unevenly. Foundations crack.

SQ-C-02Flood HazardA flood ruins stock, equipment and cold rooms. The one hazard that can destroy the whole asset at once.

SQ-D-01Terrain WorkabilityBuildings and yards need flat ground. A slope means cut and fill before anything is built.

SQ-D-04Sand Encroachment HazardDrifting sand blocks yards, doors and air intakes, and never stops arriving.

▲Factors that apply to some kinds only8

SQ-A-05Soil TextureDecides how much the ground will carry and whether it needs improving before building.

SQ-A-06Coarse FragmentsStone makes digging harder, but it also gives a firmer base. Which matters more depends on what is being built.

SQ-B-02Sodicity (ESP / SAR)Sodic soil swells and shrinks with moisture, which moves whatever sits on it.

SQ-B-05Calcium CarbonateHard carbonate layers are difficult to dig through. Below them the ground is firm.

SQ-C-01Drainage ConditionGround that does not drain leaves standing water in yards and around foundations.

SQ-C-03Waterlogging RiskSaturated ground under a slab loses bearing strength.

SQ-D-02Water Erosion HazardRunoff can undercut access roads and hard standing.

SQ-D-03Wind Erosion HazardThis matters for open yards and anything stored outside. It does not affect enclosed buildings.

These depend on what is being built. A heavy cold store on a slab asks more of the ground than an open yard or a light shed.

+Elements to add for agro-industry4

SQ-H-01Distance to productionHow far to the farms the plant serves. The single biggest factor for a packhouse or processing plant, and nothing in the framework measures it. A perfect site far from the crop is the wrong site.

SQ-H-02Road accessConnection to a road that can take heavy vehicles. Every load in and out moves by truck. Without the road the site does not work, whatever the ground is like.

SQ-H-03Power availabilityGrid connection and reliability. Cold stores fail without continuous power. This decides the site more often than the soil does.

SQ-H-04Ground bearing capacityWhat weight the ground will carry. A geotechnical measure. The soil factors in this study describe how well the ground grows plants. None of them measures how much weight it can carry.

The land evaluation routes this activity but does not decide it. Fourteen of the twenty-six factors do not apply, because nothing is grown. What settles the site is where the crop is, where the road goes and whether the power holds.

The three kinds of facility

How it works

Fresh produce arrives from surrounding farms, is graded, washed, packed and sent out. Everything moves through quickly — the building is a building things pass through quickly, rather than somewhere they are stored.

Scale and needs

Site sizeA few hectares, including the yard and space for trucks to turn

What the ground givesFirm level ground, and drainage for the yard

TrafficBusy with trucks during harvest, and quiet the rest of the year

WaterFor washing produce and cleaning down

PositionClose to the fields, because fresh produce loses quality the further it travels

What limits it

It has to be near the crop. Fresh produce cannot travel far before grading without losing value. This decides the site more than the ground does.

The road matters more than the soil. Trucks come and go all day through harvest.

It is seasonal. The building may stand idle for months, which shapes how much is worth building.

Environmental impact to watch

Wash waterWater used on produce carries soil, and sometimes residues, and needs somewhere to go.

Waste produceRejected and trimmed material accumulates fast and rots quickly in heat.

TrafficConcentrated truck movement on rural roads during the harvest weeks.

How it works

An insulated building kept refrigerated so produce can be held rather than sold immediately. It runs continuously, whether full or not.

Scale and needs

What the ground givesGround firm enough to carry a heavy insulated building

PowerThe power must run without interruption

PositionIt can be built anywhere between the farm and the market

Running patternIt runs all year round

FailureIf the power fails for a few hours, everything stored inside can spoil

What limits it

Power decides it. An unreliable supply makes the site unusable however good the ground is.

The ground has to carry weight. A loaded cold store is heavy, and uneven settlement cracks insulated panels and lets the cold out.

Gypsum in the ground is the specific risk. It dissolves and the building settles unevenly.

Environmental impact to watch

EnergyRefrigeration runs continuously. On a fossil-fuel grid this is the main environmental burden.

RefrigerantLeaks matter far more than the volume suggests.

Heat rejectedEvery cold store pushes heat out into the air around it.

How it works

Raw product is turned into something else — dates into paste, milk into cheese, grain into flour. More machinery, more water and more waste than a packhouse.

Scale and needs

Site sizeLarger, with space for storage, waste water treatment and future expansion

WaterA lot of water is used, both for processing and for cleaning

PowerPower runs continuously, and the demand is often high

PositionIt can be built further from the fields, because processed input keeps longer than fresh produce

Running patternOften runs all year, using stored or imported input

What limits it

Water supply and effluent both have to work. A plant needs clean water in and somewhere for dirty water to go. Either one missing stops the site.

Distance to the crop matters less. Processed input travels better than fresh, so these plants have more freedom in where they sit.

Environmental impact to watch

EffluentThe main issue. Processing water carries organic load and needs treating before discharge.

Solid wastePeel, pulp, husk and rejected material, in volume, all year.

Water useCompetes with agriculture for the same supply.

OdourOrganic processing and its waste streams can carry a long way in still air.

Land Management

Restoration, dune fixation and rangeland rehabilitation.

Factor routing13 govern · 3 qualify · 10 conditional

What is being evaluated

The degraded condition itself. The worse the land, the stronger the case for intervention — the assessment selects rather than excludes.

◖Factors that choose the site instead of rejecting it3

SQ-D-02Water Erosion HazardreversedReversed. Water erosion is why the land needs treating. Severe erosion selects the site rather than rejecting it.

SQ-D-03Wind Erosion HazardreversedReversed. Wind erosion is the reason to plant a shelterbelt. No wind erosion, no need for one.

SQ-D-04Sand Encroachment HazardreversedReversed. Moving sand is what dune fixation exists to stop. The worse it is, the higher the priority.

For every other activity these three are damage. Here they are the reason to act. A hectare with no erosion and no moving sand is not a candidate for restoration — there is nothing to restore.

●Factors that decide whether a planting will survive13

SQ-A-01Available Water CapacityWhether the soil holds enough water for a planting to survive without irrigation after the first years.

SQ-A-03Rooting ConditionsHow deep roots can go. Decides whether trees or only shallow-rooted cover will establish.

SQ-A-04Surface Sealing & CrustingA hard crust stops seed germinating. Direct seeding fails on sealed ground.

SQ-A-05Soil TextureDecides what will grow and how the surface behaves when it is disturbed.

SQ-B-01Salinity (ECe)Salt limits which species survive. Some native plants tolerate a great deal.

SQ-B-02Sodicity (ESP / SAR)Sodic soil sets hard and sheds water instead of absorbing it.

SQ-B-05Calcium CarbonateHard carbonate layers block roots and stop water moving down.

SQ-B-06Gypsum ContentGypsum layers are unstable and collapse when wetted.

SQ-B-07Soil pHDecides which species will establish and survive.

SQ-C-01Drainage ConditionWhether water sits or moves through. Both extremes limit what can be planted.

SQ-C-03Waterlogging RiskWaterlogged ground kills most dryland species.

SQ-D-01Terrain WorkabilitySteep ground is where erosion is worst, and also where planting is hardest.

SQ-E-01Moisture Deficit (Aridity)How dry it is. The main control on whether a planting survives once watering stops.

▲Factors that apply to some kinds only10

SQ-A-02Soil WorkabilityMatters where ground is prepared mechanically before planting.

SQ-A-06Coarse FragmentsStone makes planting slower. It also helps hold the surface in place.

SQ-B-04Toxicity Risk (Boron)Boron limits some plants. Many native species tolerate it.

SQ-C-02Flood HazardFlooding can wash away a new planting. On some sites it waters it instead.

SQ-E-02Thermal SuitabilityHeat makes it harder for a young plant to establish. Once established, it copes better.

SQ-E-03Radiation & Solar EnergySunlight is rarely a limitation anywhere in the Kingdom.

SQ-E-04Length of Growing Period (LGP)Sets the window for planting and establishment.

SQ-E-05Frost RiskFrost is a real risk in the highlands. On the plains it rarely occurs.

SQ-F-01Irrigation Demand (ETc)Only for the first years. Most plantings are watered to establish, then left.

SQ-F-02Crop Nutrient RequirementNative species are adapted to poor ground and rarely need feeding.

These depend on what is being planted and how. Direct seeding, planting nursery seedlings and simply fencing off an area to recover each ask different things of the ground.

+Elements to add for land management3

SQ-I-01Degradation severityHow far the land has already gone. The selection measure for this activity. Everywhere else a degraded reading rejects a site; here it is the reason to choose it.

SQ-I-02Natural recovery potentialWhether the land would come back on its own if left alone. Decides whether to plant, or simply to fence and wait. Cheaper and often better where seed and roots survive in the ground.

SQ-I-03Species survival without irrigationWhether a planting lives once watering stops. The crop library measures yield. Restoration only needs the plant to live, which is a different question entirely.

Here a planting counts as a success if it stays alive and covers the ground. The S1 to N2 classes were built to say how much a crop would produce. That is a different question from whether a plant survives.

Four kinds of land, four different jobs

What this land looks like

The condition being treated

Bare, loose sand that is physically travelling. Dunes and sand sheets advancing across roads, fields, canals and villages. Nothing holds the surface, so wind moves it.

Where it is found — Sand seas and their margins, and downwind of any large bare area.

How it is treated

Sand is stopped before anything is planted. Fences and mulch hold the surface still, then deep-rooted shrubs and trees are planted to keep it that way.

The work in order

The problemSand is blowing onto the land from somewhere else and burying it

First stepPut up fences and palm frond screens, and spread mulch, to stop the sand moving

ThenPlant into the surface once it has stopped moving

SpeciesPlants with deep roots that survive drought and salty ground

WateringWatered for the first few years only, then left to survive on its own

What goes wrong — Planting before the surface is held. Seedlings are buried or their roots exposed within a season.

What this land looks like

The condition being treated

Rangeland that has been grazed past recovery. The palatable plants are gone, bare ground shows between what is left, and the surface has started to seal or blow.

Where it is found — Around water points, near settlements, and anywhere stocking has stayed high through dry years.

How it is treated

Grazing is reduced or stopped so the land can recover, and native species are reseeded or planted where the seed in the soil is exhausted.

The work in order

The problemAnimals eat the plants faster than the plants can grow back

First stepReduce or stop the grazing. Nothing else works until this is done

ThenSow seed or plant seedlings where the land will not recover by itself

SpeciesNative grasses, and shrubs the animals can eat the leaves of

TimeRecovery takes several years, not one growing season

What goes wrong — Reseeding without controlling grazing. The new growth is eaten before it can set seed.

What this land looks like

The condition being treated

Ground where water is cutting the soil away. Gullies, rilled slopes and collapsing wadi banks. Every rain event takes more.

Where it is found — Sloping ground in the southwest highlands, and along wadi channels after they are cleared.

How it is treated

Water is slowed before the soil is treated. Contour banks, check dams and terracing reduce the flow, then planting holds what is left.

The work in order

The problemRain washes the soil off the land and carries it away

First stepSlow the water down using terraces, banks across the slope, and small dams

ThenPlant so the roots hold the soil in place

SpeciesPlants with deep roots and thick growth close to the ground

NoteBanks and dams fail if they are built before anyone measures how much water comes down

What goes wrong — Building structures without reducing the flow reaching them. They fill, overtop and breach.

What this land looks like

The condition being treated

Open ground that is not degrading but carries little or no vegetation. Treated to add cover, shelter and shade rather than to repair damage.

Where it is found — Around towns, along roads, beside farmland as windbreaks, and on suitable open ground.

How it is treated

Nursery seedlings are planted out and watered until their roots reach whatever moisture the site holds. After that they survive on their own or they do not.

The work in order

The problemThe land is not damaged. It simply has very few plants on it

First stepChoose plants that can live here without being watered

WateringWatered for two to three years, then left to survive on its own

SpeciesPlants native to the area, which already survive its dry climate

Test of successThe planting counts as successful if it stays alive once watering ends

What goes wrong — Choosing species that need permanent watering. They survive while irrigated and die when it ends.

Land Suitabilityfor a Named Crop

The same land data, two different factor sets

Irrigation method — how it changes which factors bite

All 26 factors — and how delivery method changes each

Land Suitability
for a Named Crop