Wind erosion control for aeolian deposits using microbial-induced carbonate precipitation

The effect of surficial microbial-induced calcite precipitation (MICP) treatment on wind erosion control of Samawah aeolian deposits was investigated by laboratory wind tunnel tests. The resilience of the treatment to degradation by moisture and temperature cyclic variations was investigated by performing an accelerated durability test. Several aeolian specimens were MICP treated with a total volume of 2, 1, or 0.5 L/m². The treatment consisted of Bacillus pasteurii bacterial suspension and 0.5M or 0.25M cementation solutions at 1:1 volumetric ratio. The treatment yielded a crust of cemented sand with 0.6–2.1% calcium carbonate and with an average thickness of 8.7–23.5 mm. Analyzing the results of wind tunnel tests with image analysis technique showed that, under the prevailing climatological conditions of Samawah, wind erosion can be efficiently mitigated with the MICP treatment. The treated aeolian showed satisfactory resilience to deterioration by cyclic variation of moisture and temperature, with a limited degradation of the cementation agent at the exposed surfaces. At the surface of the treated specimens, a sporadic transport of the surficial weakly bonded particles took place during the wind erosion test at wind velocities higher than those detected in the untreated aeolian. Qualitatively, the MICP treatment with a total volume of 2 L/m² and cementation solution concentration of 0.5M was the most beneficial treatment with respect to bond strength and depth of improvement.