Collaborative Research: RAPID: re-wiring of montane pollination networks under severe drought stress

预计2018年落基山脉西部将出现严重干旱，此前一个冬天的降雪量是有记录以来第二低的。干旱将极大地改变落基山脉生态系统中存在的物种及其相对丰度。因此，干旱提供了一个不寻常的机会来研究授粉网络（相互作用的传粉者和植物物种之间的联系）如何受到干扰的影响。这一点很重要，因为极端环境事件预计将变得越来越普遍，而授粉对维持野生植物种群和许多农作物的生产力和安全至关重要。具体来说，该项目主要关注1)生态系统中的物种在受到干扰后如何与其他物种形成新的联系；2)如何在重大干扰后预测新的连接；3)植物与传粉者关系的新模式对理解生态系统对干扰的响应的意义。这项工作将有助于更好地理解网络（包括其他生态网络，以及其他类型的网络，如经济、工程和社会网络）如何应对干扰，特别是在新连接的形成方面。该项目将利用非干旱年（2016年和2017年）现有的植物-传粉媒介网络现场数据，基于植物和传粉媒介丰度、传粉媒介之间对花朵的竞争以及植物和传粉媒介的物理性状（如体型）数据，构建并测试以机制为重点的网络结构模型。模型预测将与严重干旱年（2018年）的实地数据进行比较，其中预计存在的物种将大幅减少（例如，许多长寿的植物物种在干旱胁迫下可能不会开花），并且花和传粉媒介的相对丰度也会发生实质性变化。特别是，该项目还将评估这个新的网络模型相对于现有的替代模型的表现如何（目前没有一个模型在预测交互方面表现良好）。然后，研究人员将使用模型来评估重新布线的大量容量将如何影响系统级对扰动的反应。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。

A severe drought is expected in the western Rockies in 2018, following the second-lowest snowpack on record the preceding winter. The drought will dramatically alter which species are present in the ecosystems of the Rockies and their relative abundances. The drought thus presents an unusual opportunity to study how pollination networks (the connections between interacting pollinator and plant species) are affected by disturbances. This is important given that extreme environmental events are expected to become increasingly common and that pollination is critically important for the maintenance of both wild plant populations and the productivity and security of many agricultural crops. Specifically, this project is focused on 1) how species in ecosystems can form new connections to other species after disturbances; 2) how new connections can be predicted even following major disturbance; and 3) the implications of new patterns of plant-pollinator relationships for understanding ecosystem-level responses to disturbance. This work will contribute to better understanding of how networks (including other ecological networks, and other network types such as economic, engineered, and social networks) respond to disturbances, particularly in terms of the formation of new connections.This project will use existing plant-pollinator network field data from non-drought years (2016 and 2017) to build and test mechanism-focused models of network structure, based on plant and pollinator abundances, competition between pollinators for flowers, and data on plant and pollinator physical traits (such as body size). Model predictions will be compared with field data from the severe drought year (2018) in which it is anticipated that there will be a strong reduction in which species are present (for example, many long-lived plant species may not bloom when drought-stressed) as well as substantial changes in relative abundances of flowers and pollinators. In particular, the project will also assess how well this new network model performs relative to existing alternative models (none of which currently perform well in predicting interactions). The researchers will then use models to assess generally how substantial capacity for re-wiring will affect system-level responses to perturbations.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.