BACKGROUND AND AIMS Displacement of native plant species by non-native invaders may result from differences in their carbon economy, yet little is known regarding how variation in leaf traits influences native-invader dynamics across climate gradients. In Hawaii, one of the most heavily invaded biodiversity hotspots in the world, strong spatial variation in climate results from the complex topography, which underlies variation in traits that likely drives shifts in species interactions. METHODS Using one of the most comprehensive trait datasets for Hawaii to date (91 species and four islands), we determined the extent and sources of variation (climate, species, species origin) in leaf traits, and used mixed models to examine differences between natives and non-native invasives. KEY RESULTS We detected significant differences in trait means, such that invasives were more resource-acquisitive than natives over most of the climate gradients. However, we also detected trait convergence and a rank reversal (natives more resource-acquisitive than invasives) in a subset of conditions. There was significant intraspecific variation (ITV) in leaf traits of natives and invasives, although invasives expressed significantly greater ITV than natives in water loss and photosynthesis. Species accounted for more trait variation than did climate for invasives, while the reverse was true for natives. Incorporating this climate-driven trait variation significantly improved the fit of models that compared natives and invasives. Lastly, in invasives, ITV was most strongly explained by spatial heterogeneity in moisture whereas solar energy explains more ITV in natives. CONCLUSIONS Our results indicate that trait expression and ITV vary significantly between natives and invasives, and that this is mediated by climate. These findings suggest that although natives and invasives are functionally similar at the regional scale, invader success at local scales is contingent on climate.

中文翻译：

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夏威夷本土植物和非本土入侵者在关键气候梯度上的种内性状变异和性状策略逆转

背景和目的 非本地入侵者对本地植物物种的迁移可能是由于它们的碳经济差异造成的，但关于叶片性状的变化如何影响跨气候梯度的本地入侵者动态知之甚少。在夏威夷，世界上入侵最严重的生物多样性热点之一，气候的强烈空间变化源于复杂的地形，这是可能导致物种相互作用发生变化的特征变化的基础。方法 使用夏威夷迄今为止最全面的特征数据集之一（91 种和 4 个岛屿），我们确定了叶片性状变异的范围和来源（气候、物种、物种起源），并使用混合模型来检查本地人之间的差异和非本地入侵者。主要结果 我们检测到性状均值的显着差异，因此，在大多数气候梯度中，入侵者比本地人更需要资源。然而，我们还在一组条件中检测到特征收敛和排名反转（本地人比入侵者更喜欢资源获取）。尽管入侵物种在水分流失和光合作用方面的 ITV 显着高于本地物种，但本地物种和入侵物种的叶性状存在显着的种内变异 (ITV)。对于入侵者来说，物种比气候更能解释性状变异，而对于本地人来说，情况恰恰相反。结合这种气候驱动的特征变异显着改善了比较本地人和入侵者的模型的拟合度。最后，在入侵物种中，水分的空间异质性最有力地解释了 ITV，而太阳能解释了当地人更多的 ITV。结论 我们的结果表明，本地人和入侵者之间的性状表达和 ITV 差异很大，并且这是由气候介导的。这些发现表明，虽然本地人和入侵者在区域尺度上功能相似，但入侵者在局部尺度上的成功取决于气候。