Evaluation of the efficiency of biological improvement in controlling wind erosion

Nowadays, the destructive phenomenon of desertification and wind erosion is one of the most important environmental crises in the world, which are serious challenges to sustainable production and agricultural land management. In the present study, the effect of microbial precipitation of calcium carbonate has been studied as a biological reformer and compatible for controlling wind erosion and soil stabilization. For this purpose, erosion rate of bio-cemented samples was investigated through ….in a wind tunnel under the condition of wind velocity of (0 to 98 km hr-1) in two soil types with sandy and silty texture in a completely randomized design in three replications. Investigation of the threshold velocity of soil particle movement revealed that air dried soil particles begin to move at the velocity of 8 and 10 km hr-1 in the silty and sandy soils respectively, however, in all biological samples (MICP) particles did not move at 97 km.hr-1. The results also indicated that the weight loss of all MICP treatments at different wind velocities were significantly reduced as compare to the control. The amount of the soil loss among biological cemented samples and control treatments were dramatically different at higher velocities. So that, at velocities more than 57 km/h, soil losses indicated significantly enhancement in control, whereas in the soils which are treated by bacteria, soil losses were insignificant and approximately 2.5 kg.m-2.hr-1. The results also showed that the equal's amount of calcium carbonate and the penetration resistance of the soil surface increased significantly in MICP treatments as compare to control treatments, this event indicated the formation of a surface-resistant layer on bio-treated cement samples. In this study, the comparison of used bacteria also showed that Bacillus infantis and Paenibacillus sp3 have high efficiency in controlling wind erosion. Therefore, it seems that cementation by biological methods could be an effective way to stabilize surface particles and control soil erosion.