The Influence of Soil Properties on the Agronomic Efficacy of Rock Dust: A Comparative Analysis of a Semiarid Ultisol and Global Soil Types

ABSTRACT

Background : Enhanced rock weathering (ERW) using silicate rock dust is a promising strategy for soil remineralization and carbon dioxide removal. However, its agronomic efficacy is highly dependent on soil properties.

Aim : This study provides a comprehensive comparative analysis of the influence of soil type on the performance of rock dust, focusing on a semiarid Ultisol from a previous experiment and comparing it with data from 19 other recent (2020–2025) global studies.

Methods : A dataset of soil properties (pH, cation exchange capacity [CEC], texture, soil organic matter [SOM]) and crop responses from diverse soil orders, including Oxisols, Mollisols, Alfisols, Entisols, and Aridisols, was analyzed. Statistical analyses, including ANOVA, correlation, and principal component analysis (PCA), were performed.

Results : The results reveal significant differences in initial soil properties across soil orders, with CEC showing the highest variability ( F = 104.6, p < 0.0001). A significant positive correlation was found between clay content and crop yield increase ( r = 0.510, p = 0.0304), indicating that finer‐textured soils enhance the benefits of rock dust. Comparative analysis showed that Ultisols have a significantly higher CEC than Oxisols (72.5% higher, p < 0.001), yet Oxisols demonstrated a greater (though not statistically significant) yield response. PCA explained 85.9% of the total variance, with PC1 (62.0%) being primarily driven by CEC and pH, and PC2 (23.9%) by SOM.

Conclusion : These findings highlight that while high CEC is beneficial, the initial nutrient status and weathering intensity of soils like Oxisols may be drivers of the immediate agronomic benefits of rock dust. This research underscores the need for site‐specific recommendations for rock dust application, considering the complex interplay between soil properties and rock mineralogy.