Collaborative Research: Consequences of Climate-Induced Range Shifts on Multiple Ecosystem Functions

自然生态系统的健康运作取决于其中共存的各种物种的相互作用。不同但密切相关的物种沿着环境梯度相互取代（例如，从干到湿）。在某些情况下，新物种的功能相似，但在其他情况下，物种更替对生态系统以及向人类提供的货物和服务产生重大影响。在全球范围内，物种分布正在随着气候变化而发生变化，但人们对这些变化将如何影响生态系统知之甚少。 在过去的25年里，一项对生活在科罗拉多落基山脉高海拔池塘中的动物的连续研究表明，物种正在向更高海拔迁移。在相同的海拔高度，随着水位的变化，动物们会迁移到不同类型的池塘（永久性的还是临时性的）。 这个新项目的目标是确定这种变化如何影响生态系统功能。本科生的培训是该项目的一个关键组成部分，本科生将参与研究的各个方面。将为他们开发一个跨机构的研究实验，在那里他们可以共同研究从北卡罗来纳州到缅因州的物种范围转移的影响。还将培训一名研究生和一名博士后助理。最后，该小组将继续在每个家庭机构以及科罗拉多的落基山生物实验室进行公众宣传，大部分研究将在那里进行。该项目将测试食草动物（石蛾幼虫）的优势群体中的范围沿沿着环境梯度的变化将如何影响多个生态系统过程，包括碎屑能量向食草动物次级生产的转移、藻类吸收的碎屑结合营养物的释放、藻类对食草动物的自下而上的影响以及生态系统代谢。研究人员将使用模型、实验和来自整个池塘的比较数据来调查1）物种替换沿着永久性和海拔梯度在碎屑处理速率和对棕色的级联效应方面的功能替换程度（碎屑）和绿色（藻类）营养路径，（2）物种在同一海拔范围内跨持久性梯度迁移的相互作用以及与跨海拔范围迁移相关的相互作用;以及3）群落重组的生态系统过程的变化如何扩大到天然池塘。将对三个方面的影响进行评估：1）被动物食用的死亡植物部分的营养和能量的数量，2）有多少消耗被释放回环境并刺激藻类的生长，然后也可以食用，以及3）物种的新组合如何影响池塘的整体生产力。

The healthy functioning of natural ecosystems depends on the interactive roles of the various species that coexist in them. Different but closely related species replace each other along environmental gradients (e.g., from dry to wet). In some cases the new species function similarly, but in others species replacements have major impacts on the ecosystem and the goods and services provided to humans. Around the planet, species distributions are shifting in response to a changing climate, yet little is known about how the shifts will affect ecosystems. One continuous study over the past 25 years of the animals that live in high elevation ponds in the Rocky Mountains of Colorado shows that species are shifting to higher elevations. And at the same elevation animals are moving to different types of ponds (permanent vs. temporary) as the water regime varies. The goal of this new project is to determine how such shifts impact ecosystem function. Training of undergraduate students is a key component of the project and undergraduates will be involved with all aspects of the research. A cross-institutional research experiment will be developed for them, where they can work together to study the impacts of species range shifts from North Carolina to Maine. One graduate student and a postdoctoral associate will also be trained. Finally, the team will continue public outreach at each home institution, as well as at the Rocky Mountain Biological Laboratory in Colorado where most of the research will be conducted. This project will test how range shifts along environmental gradients in the dominant group of detritivores (caddisfly larvae) will affect multiple ecosystem processes, including the transfer of detrital energy to detritivore secondary production, release of detritus-bound nutrients for algal uptake, bottom-up effects of algae on herbivores, and ecosystem metabolism. Researchers will use models, experiments, and comparative data from whole ponds to investigate the degree to which 1) species replacements along permanence and elevational gradients are functional replacements in terms of detritus processing rates and cascading effects on brown (detrital) and green (algal) trophic paths, 2) the interactive effects of species shifts across the permanence gradient within an elevation and those associated with range shifts across elevations, and 3) how changes in ecosystem processes with community rearrangements scale up to natural ponds. Impacts will be assessed on three components: 1) the amounts of nutrients and energy from dead plant parts that are eaten by animals (detritivory), 2) how much of the consumption is released back into the environment and stimulates the growth of algae, which can then also be eaten, and 3) how new combinations of species affect the overall productivity of the ponds.