Soil microorganisms are crucial in terrestrial ecosystems, influencing carbon (C) sequestration, yet their metabolic activities are often constrained by nitrogen (N) and phosphorus (P) availability. Despite this, a global understanding of microbial nutrient limitation remains elusive. We synthesised 1245 observations from 225 articles to elucidate patterns and factors of microbial nutrient limitation. Contrary to convention, soil microbial P limitation is widespread (83.78% of observations), with N limitation mainly in temperate zones and pronounced P limitation in tropical and cold zones. Soil microbial P limitation correlates positively with mean annual precipitation and clay content, while N limitation correlates negatively with soil pH. Importantly, microbial nutrient limitation directly affects C cycling, as microbial C limitation increases with decreasing N or P limitation. This underscores the significance of microbial nutrient limitation in terrestrial C cycling and the need to incorporate it into Earth system models for accurate predictions under changing conditions.

中文翻译：

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揭示全球陆地生态系统中普遍存在的土壤微生物 P 限制


土壤微生物在陆地生态系统中至关重要，影响碳 （C） 封存，但它们的代谢活动通常受到氮 （N） 和磷 （P） 可用性的限制。尽管如此，全球对微生物营养限制的理解仍然难以捉摸。我们综合了 1245 篇文章的 225 个观察结果，以阐明微生物营养限制的模式和因素。与常规相反，土壤微生物 P 限制范围很广（占观察结果的 83.78%），其中 N 限制主要在温带地区，在热带和寒冷地区有明显的 P 限制。土壤微生物 P 限制与年平均降水量和粘土含量呈正相关，而 N 限制与土壤 pH 值呈负相关。重要的是，微生物营养限制直接影响 C 循环，因为微生物 C 限制随着 N 或 P 限制的减少而增加。这强调了微生物养分限制在陆地 C 循环中的重要性，以及将其纳入地球系统模型以便在变化条件下进行准确预测的必要性。