Despite the critical role of soil microbial communities in biomass production and ecosystem functioning, previous research primarily focussed on microbial structure without functional insights, especially for rare species. This study addresses this gap by exploring the functional potential of both abundant and rare bacterial communities across various land uses and soil groups in the Lower Namoi Valley, Australia. By integrating plant‐beneficial bacteria (PBB) and Functional Annotation of Prokaryotic Taxa (FAPROTAX) databases, we show that rare species exhibited higher alpha diversity and multifunctionality than abundant species. Cropping enhanced the biodiversity of abundant functional bacteria in fine‐textured soils, which promoted crop growth through increased PBB and carbon cycling. Conversely, rare functional bacteria exhibited consistently lower biodiversity in croplands. Random forest models and linear regression analyses identified land use as a significant factor influencing the biodiversity of rare functional bacterial communities, likely through plant–soil feedback systems. These findings underline the importance of land use in shaping bacterial community functionality and call for conservation strategies to protect soil biodiversity, especially rare species, to ensure sustainable soil ecosystems and support future food production.

中文翻译：

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土地利用和土壤群落对丰富稀有细菌群落功能多样性的影响


尽管土壤微生物群落在生物质生产和生态系统功能中起着关键作用，但以前的研究主要集中在微生物结构上，而没有功能方面的见解，特别是对于稀有物种。本研究通过探索澳大利亚下纳莫伊河谷各种土地利用和土壤群落中丰富和稀有细菌群落的功能潜力来解决这一差距。通过整合植物有益细菌 （PBB） 和原核生物分类群功能注释 （FAPROTAX） 数据库，我们表明稀有物种比丰富物种表现出更高的 alpha 多样性和多功能性。种植增强了细腻土壤中丰富功能细菌的多样性，从而通过增加 PBB 和碳循环促进作物生长。相反，稀有功能细菌在农田中的生物多样性一直较低。随机森林模型和线性回归分析确定土地利用是影响稀有功能性细菌群落生物多样性的重要因素，可能通过植物-土壤反馈系统。这些发现强调了土地利用在塑造细菌群落功能方面的重要性，并呼吁制定保护策略来保护土壤生物多样性，尤其是稀有物种，以确保可持续的土壤生态系统并支持未来的粮食生产。