Application of an affordable, eco-friendly and resistant mulch is essential in arid lands which are subjected to wind erosion. It is assumed that the addition of micro-silica improves the mechanical properties of mixtures containing Ca(OH)2 due to the chemical reaction between SiO2 in micro-silica and Ca(OH)2 in the composition of prepared mixtures as mulches. Therefore, this study aims to analyze and compare the efficiency of different microsilica-based mulches in sand stabilization. Different mixtures were prepared through combining micro-silica with clay, lime, gypsum, and cement. Data were analyzed as a factorial experiment based on completely randomized design with treatments including 1) mulch type: microsilica-clay-lime, microsilica-clay, microsilica-cement, microsilica-lime, microsilica-clay-gypsum, and microsilica-gypsum; 2) mulch thickness: one and two layers, and 3) time (7 and 60 days) in 3 replications. Penetration resistance (PR), shear strength (SS), threshold friction velocity (V), and soil loss (SL) were measured. Results revealed that except for microsilica-gypsum and microsilica-lime, other mulches could effectively control the movement of sands and improve the mechanical properties. Microsilica-clay-lime and microsilica-cement showed the highest PR (6.02 kgcm-2), SS (7.08, and 6.71 Ncm-2, respectively) and V (18.25 and 18.11 ms-1, respectively), and the lowest SL (no SL) which makes them the most suitable mulches for stabilizing drifting sands.

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