Fig. 3From: Changes in soil carbon sequestration and emission in different succession stages of biological soil crusts in a sand-binding areaSoil organic carbon (SOC) content and bulk density variation in sampling sites. Variation of soil organic carbon (SOC) content and bulk density at different sites. Different capital letters indicate significant differences at 0.05 level among different soil depths at the same site; the different small letters indicate significant differences at 0.05 level among the four sites at the same soil depthBack to article page