Purpose: Accurate estimation of the wind-erodible fraction (EF), defined as the proportion of soil particles smaller than 0.84 mm, is essential for wind erosion models such as WEQ, RWEQ, WEPS, EPIC, or APEX. Conventional rotary sieving is often impractical, which has led to the use of predictive equations. This study evaluated the equation [30] for Czech soils and developed a region-specific model.
Methods: Seventy-eight soil samples representing major soil units across the Czech Republic were analyzed for particle-size distribution, organic carbon, and carbonate content. EF was determined using the flat sieve dry-sieving method. Multiple regression analysis was applied to assess the equation [30] and construct an improved model.
Results: The equation [30] exhibited substantial bias under local conditions. The refined model identified k ey p redictors, i ncluding s and (r = 0 .58), s ilt (r = – 0.50), c lay (r = – 0.43), a nd p articularly the sand-to-clay ratio (r = 0.65), while organic carbon and calcium carbonate (CaCO₃) were insignificant. The model demonstrated high predictive performance (R² = 0.90; adjusted R² = 0.89).
Conclusion: The proposed equation provides a robust, region-specific alternative for EF estimation, significantly improving wind erosion risk assessment for Central European soils and underscoring the necessity of localized parameterization in wind erosion modeling.