Aridity modulates biogeographic distribution and community assembly of cyanobacterial morphotypes in drylands
Guo, Xiaoyu et al. (2022), Aridity modulates biogeographic distribution and community assembly of cyanobacterial morphotypes in drylands, Dryad, Dataset, https://doi.org/10.5061/dryad.95x69p8n3
The patterns of biogeographical distribution and assembly processes of microbiota are of vital importance for understanding ecological adaptation and functioning maintenance that microorganisms provide. Although the assembly of microbial communities was increasingly inspected, the role of their morphological characteristics is still poorly ascertained. Here, by integrating high-throughput sequencing and robust extrapolation of traits, we investigated taxonomic and phylogenetic turnovers of various cyanobacterial morphotypes in biocrusts, as a model system, to evaluate the contributions of deterministic and stochastic processes across a large geographic scale of drylands. The results showed that the non-heterocyst filamentous category dominated in arid ecosystems and the most abundant taxa had high tolerance against environmental fluctuations. Despite the significant distance-decay relationships of β-diversity in all categories, both species composition and phylogenetic turnover rates of unicellular/colonial cyanobacteria were higher than heterocystous and other filamentous cyanobacteria. Null model analysis of phylogenetic signals and abundance-based neutral model found that deterministic processes governed the assembly of the entire community and non-heterocyst filamentous morphotype, while stochastic processes prevailed in heterocystous and unicellular/colonial categories. However, aridity mediated the balance between determinism and stochasticity and prompted a shifting threshold among morphotypes, except heterocystous cyanobacteria. Our findings provide a unique perspective to understanding the role of microbial morphology in the community assembly, highlighting the differentiation of biogeographic distribution, environmental response, and species preference between cyanobacterial morphotypes with consideration of potential functional consequences, and therefore facilitated the prediction of biodiversity loss under climate change.
National Natural Science Foundation of China