Microbial life-history strategies shape biocrusts soil multifunctionality responses to multi-year snow-cover change

In the short- and medium-term treatment plots, lichen crusts mainly showed increases in bacterial and total microbial diversity, whereas cyanobacterial crusts mainly showed increases in fungal diversity. Microbial life-history strategies showed clear but biocrust-type-specific associations with SMF. Random forest and SEM analyses indicated that cyanobacterial-crust SMF was strongly constrained by the S strategy, although Y-related metabolic pathways were positively associated with SMF, whereas lichen-crust SMF was positively associated with the A strategy but negatively associated with the S strategy.

Soil physicochemical properties also played an important role in regulating SMF, but their effects and interactions with microbial attributes differed between the two biocrust types. Overall, this study demonstrates that altered snow conditions regulate biocrust SMF through the coupling of soil environmental changes and microbial functional responses, with the underlying regulatory pathways strongly dependent on biocrust type.