Coupling Consumer-Resource Interactions and Nutrient Spiraling in a Stream Network

这项研究的主要目的是了解河流网络位置如何影响营养循环、河流新陈代谢和消费者-资源相互作用之间的反馈。总的问题是，生物相互作用和生物化学组成在何时何地是河流网络中营养物质流动的重要决定因素，对下游生态群落有什么影响？最近关于消费者驱动的营养循环的理论表明，昆虫等河流消费者的元素含量的变化部分是由资源可获得性驱动的，部分是由于特定的生活史特征的出现，以响应沿物理变量梯度变化的环境条件。消费者和资源之间化学失衡的变化对营养通量的影响是河流研究中令人兴奋的前沿。研究人员将在几个网络位置和藻类演替期间检查溪流新陈代谢、消费者-资源相互作用和生物地球化学循环之间的反馈。他们将使用这些测量方法来评估藻类和死亡有机物的变化以及消费者-资源相互作用对多种营养物质通量的全系统影响，方法是探索它们对养分吸收和再生的具体影响。该项目及其科学伙伴关系将为文科学生提供新的和独特的机会来探索生态系统科学，并获得大型研究小组的哲学和实验室设施。

The main objective of this study is to understand how stream network position influences feedbacks between nutrient cycles, stream metabolism, and consumer-resource interactions. The overall question is where and when are biotic interactions and biological chemical makeup important determinants of nutrient flux in river networks, and what are the consequences for downstream ecological communities? Recent theory addressing consumer-driven nutrient recycling suggests that shifts in elemental content of stream consumers, such as insects, are driven in part by resource availability and in part by the emergence of specific life history traits in response to changing environmental conditions along gradients of physical variables. The effects of resulting shifts in chemical imbalances between consumers and resources on nutrient fluxes is an exciting frontier in the study of streams. The investigators will examine feedbacks between stream metabolism, consumer-resource interactions and biogeochemical cycling at several network positions and during algal succession. They will use these measurements to estimate whole-system effects of changes in algal and dead organic matter and consumer-resource interactions on fluxes of multiple nutrients by exploring their specific effects on nutrient uptake and regeneration. This project and its science partnerships will provide liberal arts students with new and unique opportunities to explore ecosystem science and access to philosophies and lab facilities of large research groups.