Diversity and distribution of soil microbiome along a climatic gradient in the Senegalese peanut basin

Understanding how soil microbial communities are impacted by climate change is critical given their diverse ecosystem services, particularly in semiarid regions of West Africa. Here, we performed Illumina‐MiSeq amplicon sequencing analysis of the gyrB and 18S rRNA genes to investigate the diversity, structure, and distribution of bacterial and arbuscular mycorrhizal fungal (AMF) communities and their main drivers along a rainfall and temperature gradient in the Senegalese peanut basin. The study revealed that the bacterial communities were dominated by the phyla Actinomycetota, Pseudomonadota, Bacillota, and Bacteroidota, whereas the fungal community was dominated by the classes Glomeromycetes, Paraglomeromycetes, and Archaeosporomycetes. Thirteen glomeromycotan genera were found within nine families ordered according to relative abundance: Glomeraceae, Paraglomeraceae, Claroideoglomeraceae, Gigasporaceae, Entrophosporaceae, Archaeosporaceae, Diversisporaceae, Acaulosporaceae, and Ambisporaceae. These taxa varied in abundance among sites. Overall, the data provided evidence that the microbial communities were influenced by the soil physicochemical properties, rainfall regimes and temperature variability. Both bacterial and AMF richness and Shannon-entropy diversity indexes decreased at the low and high rainfall sites compared to the moderate rainfall sites, with bacteria being more responsive to rainfall and temperature dynamics than AMF. The bacterial co-occurrence network was also more complex at the moderate rainfall sites, with the shorter path length among interacting epecies, suggesting higher community efficiency. The soil microbiome was shaped by a broad range of edapho-climatic factors, particularly pH, ammonium content, carbon content, soil texture, rainfall, and temperature. The Senegalese peanut basin soil microbiome is understudied and this study fills a significant knowledge gap on projected climate-induced changes in microbial communities.