Desert plant resource islands determine the abundance of live and dead soil bacterial communities

While it has become possible to distinguish viable (living) versus non-viable (dead) bacterial cells in soil samples, there has been little concerted study of the taxonomic assemblage of dead cells and how it differs from that of living cells. In this study, we aimed to determine the effect of the proximity of desert plants on the soil community in general, and particularly on the live and dead bacterial community ratio under the shelter of the plant canopy. We compared the effect of the proximity of the three desert plants, Zygophylum dumosum, Hammada scoparia and Atriplex hirtum, and in the soil crust compared to open field-bare soil as control. Our investigation revealed a notable prevalence of live bacteria from the Proteobacteria and Actinobacteria phyla across all soil samples. Interestingly, we observed a significant reduction in the dead microbial community in samples from Z. dumosum, soil crust, and control samples when compared to live bacteria, particularly in those from H. scoparia and A. halimus. This finding underscores the vital role of the microbial community in arid environments, where soil remains dry for over 90% of the year, limiting access to soluble resources. Understanding the distinction between live and dead microbial communities is essential for nutrient supply and can greatly influence plant adaptations to resource pulses. This highlights the interconnectedness of soil health, microbial activity, and plant resilience in these challenging ecosystems.