Each soil type is systematically evaluated against six core criteria: recognised identity, rarity or
restricted extent, threat or active transformation, profile integrity, scientific, ecological, cultural, or
economic significance, and irreplaceability. These evaluations assign soil to risk categories that map
directly to three operational action tiers, triggering immediate legal restrictions and dedicated soil
reserves for critical risks (Tier 1), active restoration and landholder stewardship agreements for at-risk
soil (Tier 2), and baseline mapping and monitoring for watchlist soil (Tier 3). By combining scientific
diagnosis with practical policy tools, SiLES translates soil diversity into actionable land-use planning to
safeguard non-renewable soil assets before they are permanently lost.
