Mechanical properties and erosion resistance effect of salt desert soil strengthened by indigenous microorganisms.

Using the principle of microbial mineralization to conduct research on the solidification and dust suppression of desert sandy soil has become the technological frontier in the field of desert ecological restoration in northwest China. However, the urease activity of common ureolytic microorganisms is inhibited to varying degrees in plateau environments. Therefore, screening native (indigenous) extremely excellent ureolytic microorganisms in cold and arid desert environments for solidifying desertified soil has become a new research idea in this field. In this paper, extremely excellent ureolytic microorganisms are screened from the salt desert soil in the arid area of the Qinghai Plateau. Through perfusion method, spraying method and water erosion method, solidification experimental research is conducted on the salt desert soil. The physical and chemical characteristics, mechanical strength changes and erosion resistance of the salt desert soil solidified by indigenous microorganisms are analyzed. The results show that there are extremely excellent ureolytic microorganisms (Z7) in the salt desert soil of the Qinghai Plateau. Z7 belongs to probiotics. In an environment with a salt concentration of 5%, the maximum enzyme activity of Z7 is 2.075 U/mL. The unconfined compressive strength of the salt desert soil solidified by Z7 is increased by 26.8 times. The shear strength of the surface soil is increased by about 9 times. The average surface soil loss speed is reduced by 70.5%. The erosion resistance is increased by 6.5 times. The research results indicate that indigenous ureolytic microorganisms have application potential for solidifying and resisting erosion of loose salt desert soil, providing new strategic support for ecological restoration of salt desert environments in arid plateau areas.