Evaluation of microbially Induced calcite precipitation (MICP) methods on different soil types for wind erosion control

Abstract

Application methods (i.e., pouring and mixing method) of Microbially Induced Calcite Precipitation (MICP) and its effect on wind erosion were investigated on four soil types (i.e., medium sand, fine sand, loamy fine sand and loam). With mixing method, calcite precipitated evenly throughout the upper part (0 - 5 cm) of all the soils tested, but with pouring method, only medium sand showed even calcite distribution. The reason can be ascribed to the limited permeability of MICP-inducing solution (i.e., calcium, urea and <i>Sporosarcina pasteurii</i>) through loamy fine sand and loam due to their low hydraulic conductivity (i.e., < 10<sup>-5</sup> cm/s). Moreover, bacterial penetrability was also reduced by calcium (i.e., 70 to 20%) in fine sand. Hence, pouring method for medium sand and mixing method for the others were applied with various MICP-inducing solution concentrations (i.e., 0.1 to 1 M of urea and calcium). When exposed to wind of 15 m/s after MICP application, 0.25 M solution in medium and fine sand, and 0.1 M solution in loamy fine sand and loam showed little or no soil loss. The results suggest that a proper application method be chosen considering soil properties that affect even calcite distribution to mitigate soil erosion.

Geotechnical Engineering Properties of Soils Solidified by Microbially Induced CaCO3 Precipitation (MICP)

“…e concentration threshold reduced the positive effect of the bacterial concentration on the water resistance of the surface of the sample, and the protection layer provided satisfactory durability and effectively alleviated the weathering of the ancient clay roofing tiles. Chae et al [106] found that, with a wind speed of 15 m/s, the amount of wind erosion of medium sand or fine sand after solidification using 0.5 M MICP solution was relatively small, so appropriate injection methods should be chosen to reduce soil erosion, considering the soil properties. According to the wind tunnel test results, Nikseresht et al [107] argued that an increase in penetration resistance decreased the soil loss of soil MICP solidified with vinasse and molasse to approximately onethird of that of the blank sample, indicating that the soil treated by molasse and vinasse had a high resistance to wind erosion.…”

Experimental study on tailings cementation by MICP technique with immersion curing

“…The effect of tailings cementation by the MICP was studied. Many scholars have conducted studies on repair and reinforcement of various materials, including concrete-based materials, soil and sand, by the MICP technique [ 11 , 19 , 20 ]. Surface brushing or grouting was adopted in most of the previous studies, which cannot effectively reinforce the interior of sand or soil mass.…”

Effects of Soil Surface Chemistry on Adsorption and Activity of Urease from a Crude Protein Extract: Implications for Biocementation Applications

“…Although soils generally display low levels of hydrophobicity [28,29], hydrophobic soils, defined as having contact angles ≥ 90 • , have been documented worldwide and are especially common in surface soils that often dry out or have been exposed to fires [28,[30][31][32][33][34][35][36]. It is also noteworthy that hydrophobic soils are associated with increased soil erosion [37][38][39][40], for which soil stabilization via biocementation may be a suitable mitigation method [41][42][43][44]. In addition, low amounts of adsorbed proteins and the subsequent retention of their enzymatic activity have been observed in soils containing aluminum and iron oxides, even in single-protein adsorption studies [19,22,45].…”