Department of Biology, San Diego State University, San Diego, CA 92182, USA.
Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA.
FEMS Microbiol Ecol. 2023 Oct 17;99(11). doi: 10.1093/femsec/fiad120.
Restoring ecosystems requires the re-establishment of diverse soil microbial communities that drive critical ecosystem functions. In grasslands, restoration and management require the application of disturbances like fire and grazing. Disturbances can shape microbial taxonomic composition and potentially functional composition as well. We characterized taxonomic and functional gene composition of soil communities using whole genome shotgun metagenomic sequencing to determine how restored soil communities differed from pre-restoration agricultural soils and original remnant soils, how management affects soil microbes, and whether restoration and management affect the number of microbial genes associated with carbohydrate degradation. We found distinct differences in both taxonomic and functional diversity and composition among restored, remnant, and agricultural soils. Remnant soils had low taxonomic and functional richness and diversity, as well as distinct composition, indicating that restoration of agricultural soils does not re-create soil microbial communities that match remnants. Prescribed fire management increased functional diversity, which also was higher in more recently planted restorations. Finally, restored and post-fire soils included high abundances of genes encoding cellulose-degrading enzymes, so restorations and their ongoing management can potentially support functions important in carbon cycling.
恢复生态系统需要重建多样化的土壤微生物群落,这些微生物群落驱动着关键的生态系统功能。在草原地区,恢复和管理需要应用干扰措施,如火灾和放牧。干扰因素也会影响微生物的分类组成和潜在的功能组成。我们使用全基因组鸟枪法宏基因组测序来描述土壤群落的分类和功能基因组成,以确定恢复后的土壤群落与恢复前的农业土壤和原始残余土壤有何不同,管理如何影响土壤微生物,以及恢复和管理是否会影响与碳水化合物降解相关的微生物基因数量。我们发现,恢复后的、残余的和农业土壤之间在分类和功能多样性以及组成上都有明显的差异。残余土壤的分类和功能丰富度和多样性较低,组成也明显不同,这表明恢复农业土壤并不能重建与残余土壤相匹配的土壤微生物群落。规定的火灾管理增加了功能多样性,而在最近种植的恢复区中,功能多样性更高。最后,恢复后的和火灾后的土壤中含有大量编码纤维素降解酶的基因,因此恢复区及其持续管理可能能够支持对碳循环很重要的功能。