Fig. 3

Spatial separation of microbial types close to, and away from, M. vaginatus in soil crusts. a NMDS ordination of Bray-Curtis pairwise distance computed on the Hellinger-transformed OTU composition in bulk soil or M. vaginatus cyanospheres (sans M. vaginatus), with 95% confidence ellipses drawn for each with a stress value of 0.19. In each setting, bulk soil communities differ in composition from their respective M. vaginatus cyanosphere (bundle communities). FB, Chihuahuan Desert (hot desert); HSN, Great Basin Desert (cold desert). b Frequency distribution of the ratios in relative abundance for microbial OTUs that co-occurred in the cyanospheres of M. vaginatus and in the bulk soil crusts, showing a skewed distribution towards segregation. c Differential abundance of microbial OTUs (sans M. vaginatus) in the cyanosphere vs. bulk soil crust community assessed with the DESeq2 method for cold and hot desert locations. For each OTU, the average normalized counts are plotted against their differential abundance. OTUs that were differentially abundant (p < 0.05) are represented as solid triangles and circles, while cross symbols denote those with non-significant preference. Negative values indicate enrichment in the cyanosphere and positive in the bulk soil crust