Objective This study aimed to explore the relationships between enclosure duration, soil bulk density, soil water content and soil wind erosion in desert steppes of Inner Mongolia.

Method A total of 92 flat grasslands across an area of 63000 km² were selected. Systematic sampling was adopted to investigate enclosure duration, the ¹³⁷Cs tracer method was used to determine soil wind erosion modulus, and structural equation modeling was applied to analyze interactions among the above factors.

Result The results showed that soil bulk density in free-grazing sites and sites enclosed for 1 - 3, 4 - 9, and ≥ 10 years was 1.60, 1.54, 1.55 and 1.36 g cm⁻³, respectively, with a coefficient of determination of 0.62 between bulk density and wind erosion modulus. Under enclosure condition, the coefficient of determination between bulk density and soil water content decreased with increasing soil depth. Likewise, that between soil water content and wind erosion declined with depth. Structural equation modeling revealed direct path coefficients between enclosure duration and soil bulk density of −0.267 (P  < 0.001), between enclosure duration and soil water content of 0.424 (P < 0.001), between bulk density and soil water content of −0.513 (P < 0.001), between bulk density and wind erosion modulus of 0.532, and between soil water content and wind erosion modulus of −0.406 (P  < 0.001).

Conclusion These findings indicated that enclosure suppressed wind erosion in desert steppes primarily by reducing soil bulk density and increasing soil water content.