Abstract: In this study, the disc infiltrometers were used to measure soil water infiltration under 6 kinds of treatments (the regions where there was no microbiotic crust, there was microbiotic crust, Stipa bungeana grows, S. bungeana grows with microbiotic crust, Korshinsk peashrub grows, K. peashrub grows with microbiotic crust), and the measured data were compared and analyzed. The results are as follows: (1) Microbiotic crust impeded soil water infiltration whether there was vegetation or not, and the stable infiltration rate and cumulative infiltration were higher in the regions where there was no microbiotic crust than those in the regions where there was microbiotic crust; vegetation increased the capability of resisting soil water infiltration of microbiotic crust; (2) The fitting effect with Kostiakov model under the treatment without microbiotic crust and with S. bungeana was fine; that with Philip model under the treatments without microbiotic crust, with K. peashrub and K. peashrub with S. bungeana was fine; and that of water infiltration with Horton model under all 6 kinds of treatments was fine. Therefore, Horton model can be used to describe soil water infiltration in the Loess Plateau.

Key words: microbiotic crust, soil moisture cointent, infiltration rate, cumulative infiltration, infiltration model, Shenmu County, Shaanxi Province, Loess Plateau