Sustainable Wind Erosion Control in Arid Regions: Enhancing Soil Stability Using Aluminum Chloride-Modified Soybean Urease-Induced Carbonate Precipitation Technology

In arid and semi-arid areas, soil is blown up by the wind because of its loose structure. Wind erosion causes soil quality and fertility loss, land degradation, air pollution, disruption of ecological balance, and agricultural and livestock losses. Consequently, there is an immediate imperative for methods to mitigate the impacts of wind erosion. SICP (soybean urease-induced carbonate precipitation) has emerged as a promising biogeotechnical technology in mitigating wind erosion in arid and semi-arid regions. To enhance bio-cementation efficacy and treatment efficiency of SICP, aluminum chloride (AlCl 3 ) was employed as an additive to strengthen the SICP process. Multiple SICP treatment cycles with AlCl 3 additive were conducted on Tengger Desert sand specimens, with the specimens treated without AlCl 3 as the control group. The potential mechanisms by which AlCl 3 enhances SICP may have two aspects: (1) its flocculation effect accelerates the salting-out of proteinaceous organic matter in the SICP solution, retaining these materials as nucleation sites within soil pores; (2) the highly charged Al 3+ cations adsorb onto negatively charged sand particle surfaces, acting as cores to attract and coalesce free CaCO 3 in solution, thereby promoting preferential precipitation at particle surfaces and interparticle contacts. This mechanism enhances CaCO 3 cementation efficiency, as evidenced by 2.69–3.89-fold increases in penetration resistance at the optimal 0.01 M AlCl 3 concentration, without reducing CaCO 3 production. Wind erosion tests showed an 88% reduction in maximum erosion rate (from 1142.6 to 135.3 g·m −2 ·min −1 ), directly correlated with improved microstructural density observed via SEM (spherical CaCO 3 aggregates at particle interfaces). Economic analysis revealed a 50% cost reduction due to fewer treatment cycles, validating the method’s sustainability. These findings highlight AlCl 3 -modified SICP as a robust, cost-effective strategy for wind erosion control in arid zones, with broad implications for biogeotechnical applications.