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bioRxiv · 10.1101/2023.09.26.559499

Progressive community, biogeochemical and evolutionary remodeling of the soil microbiome underpins long-term desert ecosystem restoration

Abstract

Ecological restoration of degraded lands is essential to human sustainability. Yet, an in-depth community, functional, and evolutionary microbial perspective of long-term restoration of damaged ecosystems is lacking. Herein, we comprehensively assessed the impact of long-term (up to 17 years) restoration of Tengger Desert, China, by multi-omic profiling of 1,910 topsoil samples. The soil biophysiochemical properties, especially soil hydraulics, microbiome stability, and functional diversity, significantly improved during restoration. The soil microbiome transitioned from an extreme oligotrophic and autotrophic community to a diverse copiotrophic ecosystem. The soil microbiota, including fungi, could mediate the soil physicochemical changes through metabolites. Importantly, the systematic rewiring of nutrient cycles featured the multi-domain preference of an efficient carbon fixation strategy in the extreme desert environment. Finally, the microbiome was evolving via positive selections of genes of biogeochemical cycles, resistance, and motility. In summary, we present a comprehensive community, functional, biogeochemical, and evolutionary landscape of the soil microbiome during the long-term restoration of desert environments. We highlight the crucial microbial role in restoration from soil hydraulic and biogeochemical perspectives, offering promising field applications. HighlightsO_LIThe desert soil microbiome transformed from simple oligotrophic to a diverse, stable, and nutrient-rich ecosystem with expanded functional diversity. C_LIO_LIRestoration led to systematically rewired biogeochemical cycles, which are highly efficient in carbon fixation in the desert environment. C_LIO_LIThe microbiome was evolving via positive selections of genes involved in biogeochemical cycles and environmental adaptations. C_LIO_LIMicrobes and metabolites could facilitate desert restoration from hydraulic and biogeochemical aspects, offering promising field applications. C_LI

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Chen, Q., Yuan, M., Jiang, L., Wei, X., Liu, Z., Peng, C., Huang, Z., Tang, D., Wu, X., Sun, J., Liu, Q., Zhu, X., Gao, P., Huang, L., Wang, M., Jiang, M., Jiang, C.. 2023-09-26. Progressive community, biogeochemical and evolutionary remodeling of the soil microbiome underpins long-term desert ecosystem restoration. https://doi.org/10.1101/2023.09.26.559499

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