Uniting demographic life history theory and pollination biology to understand the ecological consequences of pollinator declines

在世界范围内，传粉媒介正在减少。考虑到几乎90%的开花植物依赖于动物授粉，人们担心许多植物将与它们的传粉者一起走向灭绝。授粉很重要，因为它确保植物能够产生种子，长成新的植物，并保持物种的延续。然而，有很多理由认为，植物数量减少和传粉昆虫数量减少之间的联系并不是那么简单。例如，虽然当周围传粉者减少时，植物会产生更少的种子是有道理的，但如果新植物竞争生存的地方，种子减少并不一定意味着新植物减少。更少的种子实际上可能导致新植物之间的竞争减少，从而使更多的植物存活下来。此外，植物可能会利用其他不用于制造种子的资源来长得更大，存活时间更长，从而在其一生中有更多的繁殖机会。这些例子说明，尽管产生的种子更少，但仍然可以产生足够的新植物来维持物种的生存。一个更重要的教训是，生态是复杂的；除非你仔细观察，否则所有隐藏的策略都是不明显的。该项目将追踪数千种暴露于不同数量传粉媒介下的植物的命运，从而帮助科学家确定受传粉媒介减少影响最大的植物物种，并了解为什么其他植物存在或没有风险。除了收集数据，这个项目的科学家们还将帮助培训下一代生态学家，并将通过一部教育电影、一个博客和一个永久性的互动展览来吸引公众。基于个体的种群模型（积分投影模型）将使用田间实验数据进行参数化，其中五种多年生植物接受不同的授粉处理：(i)增加授粉，（ii）减少授粉，（iii）年际可变授粉，以及（iv）无操纵对照。所有植物都将被标记一个唯一的识别号码，并每年评估它们的人口状况。另外的发芽实验将通过密度依赖的发芽和幼苗存活来参数化授粉对招募的影响。种群模型的预测将显示授粉对植物种群动态的影响。最后，生命表响应实验将阐明授粉是否影响植物种群增长率的特定生活史机制（例如，通过生长和繁殖之间的权衡）。该项目将提供必要的经验证据，弥合传粉生物学、生活史理论和种群动力学之间的概念差距，并为理解和预测传粉媒介减少的生态后果提供一个框架。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。

Around the world, pollinators are in decline. Given that almost 90% of flowering plants rely on animal pollination, there is concern that many plants will decline towards extinction alongside their pollinators. Pollination is important because it ensures that plants can make seeds, grow into new plants and keep the species going. Yet, there are many reasons to think that the link between declining numbers of plants and declining numbers of pollinators is not so simple. For example, although it makes sense that a plant would make fewer seeds when there are fewer pollinators around, fewer seeds do not necessarily mean fewer new plants if, for example, the new plants compete for places to live. Fewer seeds could actually result in less competition among new plants, allowing more of them to survive. Furthermore, plants may use other resources not devoted to making seeds to grow larger and survive longer, thus having more chances to reproduce within their lifetime. These examples illustrate how, despite making fewer seeds, enough new plants could be made to keep the species going. A bigger lesson is that ecology is complex; all sorts of hidden strategies are not apparent until you take a closer look. This project will follow the fates of thousands of plants that are exposed to different numbers of pollinators, thereby helping scientists to identify plant species most at risk from pollinator declines and to understand why others are or are not at risk. In addition to data collection, the scientists on this project will help train the next generation of ecologists and will engage the public through an educational film, a blog, and a permanent interactive exhibit. Individual-based population models (integral projection models) will be parameterized with data from a field experiment in which five species of perennial plants receive different pollination treatments: (i) increased pollination, (ii) reduced pollination, (iii) interannually variable pollination, and (iv) an unmanipulated control. All plants will be tagged with a unique identification number and their demographic status assessed annually. Additional germination experiments will be used to parameterize the effect of pollination on recruitment through density-dependent germination and seedling survival. Projections of the population models will show the consequences of pollination for plant population dynamics. Finally, life table response experiments will elucidate specific life history mechanisms by which pollination does or does not affect plant population growth rates (e.g., via trade-offs between growth and reproduction). This project will provide the empirical evidence necessary to bridge conceptual gaps among pollination biology, life history theory, and population dynamics, as well as providing a framework for understanding and predicting the ecological consequences of pollinator declines.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.