01 · The Unit of Decision
A hectare is measured. A zone is decided.
The assessment must run at hectare resolution or it loses the precision that justifies the study. But a single suitable hectare surrounded by unsuitable ground is worth nothing — it cannot be irrigated, licensed, farmed or financed on its own. A zone is a contiguous group of hectares that share the same answers and together cover enough ground to be developed.
02 · The Hierarchy
Nation → Province → Governorate → Zone
Four tiers, each fully contained by the one above it. Every figure at a higher tier is the sum of the tier below, so a national total can always be traced down to the individual zones that produce it — and any zone can be traced up to the province that reports it.
Tier 1
Nation
Kingdom of Saudi Arabia · 215,000,000 ha
The national ledger. Total assessment area, total developable area, and the split between what is ready and what is held back. This is the figure the study reports to the Ministry.
1
▼
Tier 2
Province — منطقة
13 administrative regions
The delivery and reporting tier. Study outputs are prepared, reviewed and delivered by province — Makkah, Riyadh, Al Jouf, Asir and the rest. Regional strategy and investment targeting operate here.
13
▼
Tier 3
Governorate — محافظة
Sub-regional administrative units
The permitting and allocation tier — where a land application is actually filed and approved. This is why it constrains zone geometry: an allocation decision cannot straddle two governorates.
•••
▼
Tier 4
Zone
Contiguous · uniform · above minimum area · one governorate
The developable unit. Carries an identity, an area, a composite result and a named blocking issue where one exists. Everything above this tier is an aggregation of zones.
Z
Containment is strict in both directions. A zone belongs to exactly one governorate, a governorate to exactly one province, a province to the nation. No unit is ever split across two parents and no area is ever counted twice. This is what makes the area ledger arithmetically sound — the national total is the sum of thirteen provinces, and nothing is lost or duplicated between the tiers.
03 · How a Boundary is Drawn
Four inputs, and a break at any change
Zone boundaries are produced from four inputs. A boundary is drawn wherever any one of them changes between adjacent hectares. Crop suitability is deliberately absent from this list — it attaches to the finished zone as an attribute rather than splitting it.
Capability classC2 beside C3 → boundary
Water stateW1 beside W2 → boundary
Legal stateE1 beside E2 → boundary
Governorate lineSame ground, still splits
Why suitability is not a boundary input
If crop suitability split zones, the Kingdom would need one zone map per crop — sixty-three geometries to produce, verify, deliver and keep in step. Instead the zone is built from the three crop-independent answers, and each crop’s verdict is recorded as an attribute of it.
The consequences are all favourable: one map to hand over; crops become directly comparable because every one is measured on identical ground; adding a crop adds a column rather than redrawing geometry; and boundaries do not move when crop thresholds are recalibrated — which matters, because Saudi calibration is still outstanding.
04 · Viability Threshold
Minimum area, set by how the land would be used
There is no single minimum. A block too small for one production system may be entirely viable for another — which is why the threshold is set per system and why a fragment is never discarded outright.
Production systemMinimumBasis
Centre-pivot irrigated
50 ha
One pivot covers 50–125 ha. Below one full circle the capital cost per hectare rises sharply and the system cannot be operated efficiently.
Rain-fed & supplementary
20 ha
Yield varies year to year with rainfall. Area is what averages that variance into a predictable return.
Orchard & perennial
10 ha
Harvest crews, grading and cold-chain handling do not amortise below roughly ten hectares of mature planting.
Protected agriculture
2 ha
Very high value per square metre. A two-hectare greenhouse block is a viable commercial unit.
Rangeland & grazing
1,000 ha
Carrying capacity in arid rangeland is low. Meaningful grazing management needs scale measured in thousands of hectares.
Centre-pivot irrigated
Rain-fed & supplementary
Orchard & perennial
Protected agriculture
Rangeland & grazing
The 500× spread is the point
The largest minimum is five hundred times the smallest. A six-hectare block is invisible to centre-pivot wheat and a perfectly good commercial greenhouse site. A four-hundred-hectare block supports pivot irrigation and is far too small to manage as rangeland.
So the same zone map, read against different production systems, produces genuinely different inventories of developable land. The map does not change; the question does.
05 · Below the Threshold
Fragments are kept and flagged
A block that falls below the minimum for a given production system is not deleted. Three approaches were considered; the third is used.
Discard the fragment
NOT USED
Produces the cleanest map, and destroys real land. A fragment unviable for one system is often viable for another, so deleting it at the geometry stage throws away information the production-system layer would have recovered.
Absorb into the neighbour
NOT USED
Preserves the area but breaks Condition A. The merged zone would no longer be uniform, so a single management plan would no longer apply across it — which is the whole reason zones exist.
Retain and flag
IN USE
The fragment keeps its geometry, its answers and its area, and carries a flag recording which production systems it is too small for. Nothing is lost, uniformity holds, and viability becomes a question asked of the zone rather than a filter applied before anyone can ask.
06 · What a Zone Carries
The zone record — and the line that gets acted on
Every zone holds an identity, a geometry and a result. The field that matters most to a ministry is the last one: what is blocking this zone, and can it be moved.
Z-MKH-LTH-0147
0147
Sequence within
governorate
Area
1,840 ha · 1,840 assessed hectares merged
Composite
C2s · W2y · E2(ET)
Capability
Class 2 — moderate limitation, soil physical (s). Effective rooting depth restricted by a shallow calcrete horizon.
Water
State 2 — usable but constrained (y). Non-renewable aquifer with a declining level trend; abstraction is allocated but not open-ended.
Legal
E2 — resolvable. No cadastral record exists for the parcel. Nothing prohibits development; ownership must be established before allocation.
Viable for
Centre-pivot · orchard · protected · rain-fed — above minimum area for all four
Crop verdicts
S2z date palm, irrigated orchard
S3z wheat, centre pivot
N1z tomato, open field
Governing limit
Soil salinity — ECe 7.2 dS/m. This single reading sets the suitability class for all three crops, and explains why the three verdicts differ: date palm tolerates it, wheat is marginal, tomato is not currently viable.
Blocking issue
Tenure unrecorded — resolvable. This zone is physically capable, adequately watered and legally unencumbered. It is held back by a missing document, not by anything in the ground.
Why the blocking issue is recorded separately
A zone can fail for reasons that are permanent and reasons that are administrative, and the two look identical if both are simply reported as “unavailable”. A military exclusion zone cannot be moved. A missing ownership record can.
Recording the cause turns the assessment from a description of the Kingdom into a work programme — because the total area of land that is capable, watered and waiting only on a document is a number the Ministry can act on directly.
07 · The Output
The area ledger — the study’s headline answer
The deliverable is not the map alone. It is the map together with an area ledger that sorts every zone by whether it can be developed now, and if not, what is stopping it. The ledger is produced at every tier — nation, province and governorate — from the same underlying zone records.
CategoryZonesArea (ha)Share
Ready now
Capable, watered and legally clear. Development can proceed on existing findings.
pending
pending
pending
Blocked on paperwork only
Capable and watered. Held solely by an E2 finding — unrecorded tenure or a zoning approval. The most actionable figure in the study.
pending
pending
pending
Blocked on water
Capable and legally clear, but the water answer is W3 or W4 — allocation, sustainability or quality is the constraint.
pending
pending
pending
Marginal — viable with investment
S3 for the crops assessed. Productive with amendment, drainage or a change of crop, at a cost that must be appraised separately.
pending
pending
pending
Not developable
CN, W4 or E3. Prohibited, not usable, or physically incapable — recorded so the exclusion is auditable rather than silent.
pending
pending
pending
The second row is the finding this study exists to produce. Land that is physically capable, adequately watered, and waiting only on a document is not a constraint of the Kingdom’s geography — it is a backlog. Its size tells the Ministry precisely where cadastral work would unlock the most agricultural potential, and it is visible only because tenure is recorded as its own state rather than folded into either available or excluded.
One ledger per production system
Because the minimum viable area differs by production system, the ledger is produced once per system. The same national zone map yields a different developable inventory depending on whether the question is about centre-pivot cereal, orchard, protected agriculture or rangeland — and comparing those inventories is itself a planning output.
08 · Status
What is settled, and what is not
Settled. The hierarchy and its containment rules; the four boundary inputs; the crop-agnostic principle; the retain-and-flag treatment of fragments; the zone record structure; and the ledger categories.
Not yet settled. The minimum viable areas above are working figures and require confirmation against the Terms of Reference and Saudi commercial practice. The governorate layer must be sourced from MOMRAH before geometry can be produced. And no area figure in this module is computed — every value is marked pending until the national run is complete.