Nitrogen (N)-fixing plants are an important component of global plant communities, but the drivers of N-fixing plant diversity, especially in temperate regions, remain underexplored. Here, we examined broad-scale patterns of N-fixing and non-fixing plant phylogenetic diversity (PD) and species richness (SR) across a wide portion of temperate North America, focusing on relationships with soil N and aridity. We also tested whether exotic species, with and without N-fixing symbiosis, have fewer abiotic limitations compared with native species.

中文翻译：

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干旱驱动北美固氮植物的系统发育多样性和物种丰富度模式

固氮植物是全球植物群落的重要组成部分，但固氮植物多样性的驱动因素，特别是在温带地区，仍未得到充分探索。在这里，我们研究了北美温带大部分地区的固氮和非固氮植物系统发育多样性 (PD) 和物种丰富度 (SR) 的广泛模式，重点关注与土壤氮和干旱的关系。我们还测试了与本地物种相比，有和没有固氮共生的外来物种是否具有更少的非生物限制。