CAREER: Energy fluxes and community stability in a dynamic, high-latitude kelp ecosystem

高纬度海带森林支持着丰富的生态和经济上重要的物种，缓冲海岸线免受高能风暴的影响，并通过隔离和储存大量碳在海洋碳循环中发挥关键作用。了解这些海藻群落的能量通量和消费者-资源相互作用如何变化，对于制定有助于维持这些有价值的生态系统服务的稳健管理策略至关重要。在这个综合研究和教育计划中，项目团队将调查消费者群体如何对温度、碳酸盐化学和资源质量的变化做出反应，从而影响海带森林的食物网和生态系统稳定性。在阿拉斯加东南部的巨型海带（Macrocystis pyrifera）的北部范围范围内进行的一套综合研究将研究海带群落如何应对由季节变化、海洋温度变化和酸化条件引起的可变环境条件。作为该项目的一部分，本科生和高中生将通过以下方式接受全面培训：(1)在阿拉斯加州锡特卡湾的沉浸式实地课程，(2)密集的、有指导的研究实习，以及(3)科学传播和公众宣传方面的体验式培训，其中包括通过播客、公开讲座和广播传播研究成果的各种机会。消费者-资源的相互作用构成了食物网并控制着生态系统的稳定性，然而，我们对这些重要的相互作用在未来气候条件下如何变化的理解，受到营养水平内部和之间多重压力因素直接和间接影响的复杂性的阻碍。例如，初级生产者营养质量和化学威慑方面的环境介导变化有可能改变初级生产者和消费者之间的草食率和能量流动，从而影响生态系统的稳定性。此外，全球变化对初级生产者的影响可能取决于其他有限资源，如光照和养分，这些资源在动态、温带和高纬度生态系统中随季节变化。在高纬度的海洋生态系统中，气候模型预测，海洋酸化在初级生产受到光照限制的冬季最为明显。这个项目是建立在这样一个假设之上的：在冬季，气候变暖和海洋酸化可能导致初级消费者的能量需求与资源的可用性和质量不匹配，并对未来的营养结构和生态系统稳定性产生连锁效应。通过补充性的实验室和实地实验，项目团队将确定1)温度和碳酸盐化学如何结合起来影响各种物种的主要消费者生物能量学；2)海洋酸化和变暖对主要消费者的间接影响，通过环境介导的不同季节初级生产者的可用性、营养质量和适口性的变化。利用实验室和野外实验数据，项目团队将构建一个模型，分析在季节性动态的高纬度环境中，变暖和海洋酸化对营养结构和生态系统稳定性的紧急影响。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。

High latitude kelp forests support a wealth of ecologically and economically important species, buffer coastlines from high-energy storms, and play a critical role in the marine carbon cycle by sequestering and storing large amounts of carbon. Understanding how energy fluxes and consumer-resource interactions vary in these kelp communities is critical for defining robust management strategies that help maintain these valuable ecosystem services. In this integrated research and education program, the project team will investigate how consumer populations respond to variability in temperature, carbonate chemistry and resource quality to influence the food webs and ecosystem stability of kelp forests. A comprehensive suite of studies conducted at the northern range limit for giant kelp (Macrocystis pyrifera) in SE Alaska will examine how kelp communities respond to variable environmental conditions arising from seasonal variability and changing ocean temperature and acidification conditions. As part of this project, undergraduate and high school students will receive comprehensive training through (1) an immersive field-based class in Sitka Sound, Alaska, (2) intensive, mentored research internships, and (3) experiential training in science communication and public outreach that will include a variety of opportunities to disseminate research findings through podcasts, public lectures and radio broadcasts. Consumer-resource interactions structure food webs and govern ecosystem stability, yet our understanding of how these important interactions may change under future climatic conditions is hampered by the complexity of direct and indirect effects of multiple stressors within and between trophic levels. For example, environmentally mediated changes in nutritional quality and chemical deterrence of primary producers have the potential to alter herbivory rates and energy fluxes between primary producers and consumers, with implications for ecosystem stability. Moreover, the effects of global change on primary producers are likely to depend on other limiting resources, such as light and nutrients, which vary seasonally in dynamic, temperate and high latitude ecosystems. In marine ecosystems at high latitude, climate models predict that ocean acidification will be most pronounced during the winter months, when primary production is limited by light. This project is built around the hypothesis that there could be a mismatch in the energetic demands of primary consumers caused by warming and ocean acidification and resource availability and quality during winter months, with cascading effects on trophic structure and ecosystem stability in the future. Through complementary lab and field experiments, the project team will determine 1) how temperature and carbonate chemistry combine to affect primary consumer bioenergetics across a diversity of species and 2) the indirect effects of ocean acidification and warming on primary consumers via environmentally mediated changes in the availability, nutritional quality and palatability of primary producers across seasons. Using the data from the laboratory and field experiments, the project team will 3) construct a model of the emergent effects of warming and ocean acidification on trophic structure and ecosystem stability in seasonally dynamic, high latitude environments.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.