Photosynthetic basis of temperate plant invasions: a pan-hemisphere comparison of leaf function

入侵植物每年花费数百万美元用于控制和根除工作，并且是对生物保护和自然区域管理的最普遍威胁之一。然而，只有一小部分引入的植物实际上成为问题，入侵物种管理的最大挑战之一是确定某些物种是否“预先适应”入侵-也就是说，在它们的家园范围内，在它们被引入之前，可能会将它们识别为潜在的威胁。该项目比较了超过40种入侵植物在美国东北部和欧洲和亚洲类似气候下的家园和入侵范围内的表现。结合叶片化学和结构的实验室测试，研究人员将确定入侵植物是否在其入侵范围内发生变化，使它们能够更好地与原生植被竞争，或者它们是否已经在其家园范围内拥有这些竞争属性。在多个生境中对大范围物种进行实地和实验室测量的结合将提供一套独特的数据，以确定对叶功能的主要限制。该项目通过研究实验室之间的高级人员，研究生和博士后同事的交流促进国际知识转移和研究伙伴关系。结果将有助于土地管理的做法，通过更好地了解非本地植物的成功入侵背后的机制。该项目通过增加“锡拉丘兹全球变化花园”（锡拉丘兹校园内的教育植物园）的资源开发和外联活动，加强STEM教育。该项目从两个互补的角度探讨入侵植物物种的生态优势机制。首先，研究人员将确定不同光合能力的植物如何将关键限制资源（氮）分配给不同的叶功能（光捕获，碳固定，细胞壁结构，防御化合物），以测试氮分配是否驱动同化率，以及入侵者是否比共存的本地物种具有更高的同化分配。其次，研究人员将确定入侵物种是否已经改变了它们在入侵范围内的同化率分配，以应对天敌的减少，或者由于不同的区域进化历史，光合优势是否已经存在于它们的原生范围内。最后，研究人员将通过实验测试光合性能是否是入侵者竞争优势的主要驱动力。该项目将是第一个在大量物种和栖息地（森林和野外环境）中经验性地测试入侵和叶分配理论的项目，并在生理水平上测试物种入侵的“预适应”理论。该项目还将通过确定在入侵范围内是否普遍发生叶功能的变化，以及这些过程是否足以改变与本地物种的相互作用来推进我们对入侵过程的理解。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

Invasive plants cost millions of dollars annually in control and eradication efforts and are among the most pervasive threats to biological conservation and natural area management. However, only a small percentage of introduced plants actually become problems, and one of the biggest challenges in invasive species management is to identify whether some species are 'pre-adapted' to invade - that is, have attributes in their home range that may identify them as potential threats before they are introduced. This project compares the performance of over 40 species of invasive plants in their home and invaded ranges across fields and forests in the Northeast U.S. and in similar climates of Europe and Asia. Combined with laboratory tests of leaf chemistry and structure, the investigators will determine whether invasive plants change in their invaded range in ways that make them better able to compete with native vegetation, or whether they already possessed these competitive attributes in their home range. The combination of field and laboratory measurements across a large range of species in multiple habitats will provide a unique set of data to identify the main constraints on leaf function. The project fosters international knowledge transfer and research partnerships through exchanges of senior personnel, graduate students, and postdoctoral associates between research labs. Results will contribute to land management practices through a better understanding of mechanisms behind successful invasions of non-native plants. The project enhances STEM education by increasing resource development and outreach activities for the "Syracuse Global Change Garden", an education-based arboretum on the Syracuse campus.This project addresses the mechanism of ecological advantage of invasive plant species from two complementary angles. First, researchers will determine how plants of different photosynthetic capacity allocate a key limiting resource (nitrogen) to different leaf functions (light harvesting, carbon fixation, cell wall structure, defensive compounds) to test whether nitrogen allocation drives assimilation rate, and whether invaders have higher allocation to assimilation than co-occurring native species. Second, researchers will determine whether invasive species have altered their allocation to assimilation rate in their invaded range in response to reduced natural enemies, or whether photosynthetic advantages were already present in their native range due to different regional evolutionary histories. Finally, the investigators will test experimentally whether photosynthetic performance is the principal driver of competitive dominance in invaders. This project will be among the first to test invasion and leaf allocation theory empirically across a large number of species and habitats (forest and field environments), and to test the 'pre-adaptation' theory of species invasions at a physiological level. The project will also advance our understanding of invasion processes by determining whether shifts in leaf function commonly occur in the invaded range, and whether such processes are sufficient to alter interactions with native species.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.