Induced biological soil crusts and soil properties varied between slope aspect, slope gradient and plant canopy in the Hobq desert of China

Cyanobacterial inoculation can accelerate the formation of induced biological soil crusts (IBSCs) and is suggested as an effective strategy for desertification reversal. However, previous studies concerning the spatial distribution of IBSCs at the micro scale are insufficient. In this study, IBSCs distributed in microhabitats differing in slope aspect, slope gradient and plant cover were investigated to reveal the effects of microhabitats on soil properties and IBSC development. There are significant differences in soil environmental factors including microclimates and soil physical properties, and soil component factors including SOC, TN, TP and dissolved organic matter components among sites with different microhabitats. Compared with IBSCs on south-facing slopes and in interspaces, those under plant cover and on north-facing slopes were characterized by higher biomass and moss abundance, indicating later successional stages. The relative contributions of microhabitat characteristics to the variance in environmental conditions and soil properties were slope aspect (59.5%) > shrub cover (13.8%) > slope gradient (6.2%). Furthermore, these environmental and soil component factors contributed equally and interactively to IBSC development. Our findings reveal that soil environmental factors and soil composition affected by microhabitats drive the distinct development of IBSCs in interactive and essential ways. More attention should be paid to these microhabitat-related soil factors in the IBSC rehabilitation and maintenance engineering.