Summary Elton's biotic resistance hypothesis predicts that biodiversity can resist the establishment of invasive plants. However, whether and how within‐species diversity mediates the impacts of successfully established invaders is poorly understood, particularly in the face of climate change. We used an experimental system to test the effect of intraspecific diversity of a native foundation species, Scirpus mariqueter, on the soil‐legacy impacts of a global plant invader, Spartina alterniflora, under well‐watered and drought conditions. We found that more diverse populations of the native plant buffered against the negative soil‐legacy impacts of the invader on the native plant. This intraspecific diversity effect was due to a complementarity effect triggered by invader‐shaped soil biota, and emerged in both well‐watered and drought conditions. Compared with the previous finding that intraspecific diversity of the native plant can reduce the performance of the invader through soil biotic feedbacks, this study provides further evidence that it helps to mitigate the negative soil‐derived impacts of the invader. These findings together emphasize the need for management measures that promote and restore native intraspecific diversity in a changing world.

中文翻译：

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种内多样性减轻了入侵植物对土壤遗产的负面影响


总结 埃尔顿的生物抗性假说预测，生物多样性可以抵抗入侵植物的建立。然而，物种内多样性是否以及如何介导成功建立的入侵者的影响知之甚少，尤其是在面对气候变化时。我们使用实验系统来测试本地基础物种 Scirpus mariqueter 的种内多样性对全球植物入侵者 Spartina alterniflora 在浇水和干旱条件下的土壤遗产影响的影响。我们发现，更多样化的本地植物种群可以缓冲入侵者对本地植物的负面土壤遗产影响。这种种内多样性效应是由于入侵者形状的土壤生物群引发的互补效应，并且在浇水充足和干旱的条件下都出现。与之前发现本地植物的种内多样性可以通过土壤生物反馈降低入侵者的性能相比，本研究提供了进一步的证据，表明它有助于减轻入侵者对土壤的负面影响。这些发现共同强调了在不断变化的世界中促进和恢复本地种内多样性的管理措施的必要性。