Macrofauna functional diversity microbial comunities and drought stress experiment

The impacts of climate change on terrestrial ecosystems require a better understanding of the interactions between different soil communities to maintain their functionality. Soil fauna and their relationship with the soil microbiome enable the identification of responses to biotic and abiotic stress. Drought represents one of the main threats originating from climate change. This study examined the effect of high and low functional diversity of soil fauna on soil microbial communities under prolonged drought conditions using 16S amplicon sequencing and estimated annotation of functional genes. The experiment was conducted over two years using 16 mesocosm units subjected to drought treatments. Our results show that the relative abundance of Gram-positive bacterial communities increased compared to Gram-negative during drought periods, with particular taxa exhibiting drought-resistant traits. Furthermore, our results indicate that higher levels of fauna functional diversity can help buffer the effects of drought on microbial diversity and composition. The capacity of microbial communities to face drought conditions was reflected in the enrichment of drought-tolerant genes in specific bacterial taxa. These findings support the need to preserve soil biodiversity to mitigate the effects of future drought on soils.