WORLD A — LAND, AGRICULTURE & FARMING FOUNDATIONS · REALM 03
Land Capability
Land Capability Classification · Soil, Slope & Drainage Factors · Land-Use Planning (36 Micro-Realms)
ECONOMIC GEOGRAPHY
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REALM 02: LAND USE
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SOIL + SLOPE + DRAINAGE
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LIMITATION GRADING (e, w, s, c)
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LCC CLASSES I TO VIII
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OPTIMAL LAND-USE PLANNING
SUB-WORLD I — LAND CAPABILITY CLASSIFICATION (LCC) SYSTEM
USDA & AISLUS 8-Class Hierarchy (03.01 – 03.10)
MICRO-REALM 03.01
LCC Architecture
- Inherent biophysical capacity
- Permanent limitation grading
- Eight-tier Roman numeral scale
Class I: Prime Arable
- Zero or negligible limitations
- Deep well-drained level soils
- Intensive multi-crop suitability
Class II: Good Arable
- Moderate soil/slope limits
- Gentle 1–3% gradients
- Requires contour tillage
Class III: Moderately Good
- Severe erosion/water hazards
- Restricted crop choice
- Intensivegraded bunding needed
Class IV: Marginal Arable
- Very severe cultivation limits
- Occasional ley-farming only
- Boundary of arable agriculture
Class V: Non-Arable Flats
- Zero erosion, non-tillable
- Bouldery or flooded bottoms
- Pasture & wetland forestry
Class VI: Grazing & Forestry
- Steep 15–25% slopes
- Shallow erosion-prone soils
- Regulated rotational grazing
Class VII: Fragile Woodland
- Very steep >25% gradients
- Skeletal lithic soils
- Strict protection afforestation
Class VIII: Watershed & Wildlife
- Zero commercial plant harvest
- Alpine peaks, cliffs, deserts
- Biodiversity & catchment shield
Subclasses (e, w, s, c)
- e: Erosion & runoff risk
- w: Wetness & drainage excess
- s: Root-zone soil; c: Climate
SUB-WORLD II — SOIL FACTORS IN CAPABILITY ASSESSMENT
Edaphic & Root-Zone Determinants (03.11 – 03.19)
MICRO-REALM 03.11
Effective Soil Depth
- Deep (>90 cm) Class I–II
- Shallow (<22.5 cm) Class VI–VII
- Hardpan root-zone barrier
Surface Soil Texture
- Loam workability optimum
- Coarse sand droughtiness
- Heavy clay tillage drag
Subsoil Permeability
- Hydraulic conductivity rate
- Claypan percolation block
- Root aeration oxygen balance
Stoniness & Outcrops
- Gravel & cobble volume %
- Ploughshare breakage hazard
- Mechanization exclusion limit
Nutrient Retention & CEC
- Cation exchange capacity
- Base saturation percentage
- Fertilizer response efficiency
Salinity & Sodicity (s)
- Electrical conductivity (ECe)
- Exchangeable sodium % (ESP)
- Osmotic root stress
Soil Reaction (pH Limits)
- Acidic aluminum toxicity (<5.5)
- Alkaline nutrient lockup (>8.5)
- Liming & gypsum amendment
Available Water Capacity
- Field capacity minus wilting
- Dry-spell buffering power
- Rainfed capability determinant
Soil Erodibility (K-Factor)
- Aggregate structural stability
- Silt-fine sand detachment
- Organic matter binding
SUB-WORLD III — SLOPE, RELIEF & DRAINAGE FACTORS
Topographic & Hydrological Controls (03.20 – 03.28)
MICRO-REALM 03.20
Slope Gradient Thresholds
- 0–1% Class I; 1–3% Class II
- 3–5% Class III; 5–10% Class IV
- >15% Non-arable Classes VI–VIII
Slope Length & Aspect
- Runoff kinetic momentum (LS)
- Sunny vs shady slope aspect
- Evapotranspiration moisture loss
Micro-Relief & Undulation
- Hummocky surface irregularity
- Laser land-leveling cost
- Gravity irrigation uniformity
Sheet & Rill Erosion (e)
- Topsoil A-horizon stripping
- Finger-like rill incisions
- Downgrades Class I to IIIe/IVe
Gully & Ravine Hazard
- Deep V-shaped chasm dissection
- Badland topography (Chambal)
- Relegates land to Class VIe/VIIe
Surface Drainage Network
- Drainage density & outlets
- Depressional ponding basins
- Stormwater evacuation speed
Internal Drainage Classes
- Excessively vs well drained
- Imperfectly to poorly drained
- Subsurface tile-drainage need
Waterlogging Hazard (w)
- Shallow perched water table
- Anaerobic root suffocation
- Canal-command seepage zones
Flood Inundation Risk
- Active Khadar floodplain risk
- Return-period flash flooding
- Restricts land to Class Vw
SUB-WORLD IV — LAND SUITABILITY & SPATIAL LAND-USE PLANNING
FAO Framework, GIS & Zoning (03.29 – 03.36)
MICRO-REALM 03.29
Capability vs Suitability
LCC
FAO
- Broad LCC vs crop-specific FAO
- Orders: Suitable (S1–S3) vs N
- Tea on slopes: Class VI, S1
Agro-Ecological Zoning
- Length of growing period (LGP)
- Bioclimate + soil + physiography
- 20 NBSS&LUP AEZs in India
Watershed Land Planning
- Ridge-to-valley treatment
- Upper ridge Class VI–VII forest
- Valley floor Class I–II crops
Capability-Matched Allocation
- Eliminating land-capability mismatch
- Retiring steep marginal ploughland
- Zero-degradation intensity ceiling
Prime Farmland Protection
- Ring-fencing Class I & II soils
- Diverting industry to wastelands
- Agricultural preservation belts
Hazard & Eco-Zoning
- Floodplain & landslide exclusion
- Eco-Sensitive Zones (ESZ)
- Coastal Regulation Zone (CRZ)
GIS Multi-Layer Overlay
- DEM slope + soil + drainage
- Analytic Hierarchy Process (AHP)
- Cadastral parcel-level decision
Integrated Land-Use Plan
- National Land Use Boards
- Participatory micro-level planning
- Intergenerational land security
Core Ontological Distinctions
Land Capability (USDA) vs. Land Suitability (FAO)Land Capability grades land broadly (Classes I–VIII) by its negative physical limitations for general arable field crops. Land Suitability (FAO S1, S2, S3, N1, N2) evaluates fitness for a specific, defined use (e.g., a 15% hill slope is poor Capability Class VI for wheat, but Prime Suitability S1 for tea plantations).
Arable Classes (I–IV) vs. Non-Arable Classes (V–VIII)Classes I to IV are physically capable of mechanical ploughing and cultivation with progressively stricter conservation measures. Classes V to VIII must never be ploughed for field crops—they are restricted to pasture, forestry, watershed protection, and wildlife.
Capability Class (I–VIII) vs. Capability Subclass (e, w, s, c)The Class reveals the degree/severity of limitation, whereas the Subclass letter (`e` = erosion/slope, `w` = wetness/drainage, `s` = root-zone soil depth/salinity/stoniness, `c` = climate) reveals the dominant kind of limitation (Class I has no subclasses).
The Land Capability Planning Engine
Aligning human land use with biophysical carrying limits.
SOIL + SLOPE + DRAINAGE AUDIT
↓ Limitation Diagnosis (e, w, s, c)
CLASSES I–IV: ARABLE CULTIVATION
↓ Steep / Wet / Skeletal Threshold
CLASSES V–VIII: PASTURE, FOREST & ECO
↓ GIS + FAO Suitability Synthesis
SUSTAINABLE SPATIAL LAND PLAN