CAREER: Lakes on a Changing Landscape: A Disturbance Phenology for Phytoplankton Communities and Ecosystem Function

职业：景观变化中的湖泊：浮游植物群落和生态系统功能的干扰物候学

• 批准号: 2144197
• 负责人: Ana Morales-Williams
• 金额: $ 80.93万
• 依托单位: University of Vermont & State Agricultural College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2144197&HistoricalAwards=false
• 关键词: CAREER; Lakes; Changing; Landscape; Disturbance

Algae in freshwater lakes are sentinels of environmental change because they respond rapidly to disturbances. As they respond to disturbance, algae alter their surrounding environment through fluctuations in their growth, the processing of carbon and nutrients, and biotic interactions. This makes algae important mediators of lake ecosystem functions such as nutrient cycles and gas exchange. In the past, the regular seasonality of lake ecosystem processes made it possible to predict the composition of algal communities and the traits that influence lake ecosystem function. Lake ecosystems, however, are changing rapidly in response to multiple interacting environmental change disturbances, making previously predictable seasonal processes such as ice cover, evaporation, and run-off increasingly uncertain and chaotic. This project will identify algal traits that confer persistence across a gradient of disturbance intensity over short and long timescales. This project seeks to understand how algal communities form and influence ecosystem function, not as a disruption to expected stable conditions, but as a fluctuating, dynamic process. As part of this CAREER proposal, the research will be integrated into undergraduate curriculum and will train undergraduates, a graduate student, and a postdoctoral researcher using collaborative team science approaches. Through a partnership with lake managers and professional workshops, findings will be communicated with stakeholders and translated into management action. This CAREER award aims to describe a disturbance phenology framework for phytoplankton community assembly that is scalable across space and time in order to predict feedbacks and threshold shifts for lake ecosystem function. First, the project will seek to understand the heterogeneity of algal responses to stressors across nearshore benthic and open water pelagic vertical zones to better predict ecosystem scale response to stochastic events. Across lake zones, synchronous fluctuations of phytoplankton communities are expected to amplify and destabilize ecosystem function, measured as lake metabolism, carbon dioxide, and methane flux. Second, the project will investigate phytoplankton traits that confer persistence across time scales, and will test the hypothesis that traits which confer persistence in response to short term, stochastic disturbance such as dormancy or alternative metabolic strategies will be recruited to communities over multi-decadal time scales. Hypotheses will be tested across scales in laboratory microcosms, outdoor mesocosms, and using modern and paleolimnological approaches across a trophic gradient in five lakes. Experimental mesocosms, high-frequency sensor arrays, and microscopy facilities will be integrated into undergraduate limnology, phycology, and ecosystem ecology curriculum aimed at training students in team science, experimental design, and ecological theory. This project is jointly funded by the Population and Community Ecology Cluster and Ecosystem Science Clusters in the Division of Environmental Biology and the Established Program to Stimulate Competitive Research (EPSCoR).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.

淡水湖泊中的藻类是环境变化的哨兵，因为它们对干扰反应迅速。当它们对干扰作出反应时，藻类通过其生长、碳和营养物质的处理以及生物相互作用的波动来改变其周围环境。这使得藻类成为湖泊生态系统功能的重要媒介，如营养循环和气体交换。过去，湖泊生态系统过程的季节性规律使得预测藻类群落组成和影响湖泊生态系统功能的特征成为可能。然而，湖泊生态系统正在迅速变化，以应对多种相互作用的环境变化干扰，使以前可预测的季节性过程，如冰盖，蒸发和径流越来越不确定和混乱。该项目将确定在短期和长期时间尺度上，在干扰强度梯度上赋予持久性的藻类特征。该项目旨在了解藻类群落是如何形成和影响生态系统功能的，不是破坏预期的稳定条件，而是作为一个波动的动态过程。作为这个职业生涯的建议的一部分，研究将被纳入本科课程，并将培养本科生，研究生，和博士后研究人员使用协作团队科学的方法。通过与湖泊管理者和专业研讨会的伙伴关系，将与利益攸关方交流调查结果，并将其转化为管理行动。该CAREER奖旨在描述浮游植物群落组装的干扰物候框架，该框架在空间和时间上可扩展，以预测湖泊生态系统功能的反馈和阈值变化。首先，该项目将寻求了解近岸底栖和开放水域中上层垂直带藻类对压力源反应的异质性，以更好地预测生态系统对随机事件的反应。在整个湖区，浮游植物群落的同步波动预计将放大和破坏生态系统功能，衡量湖泊代谢，二氧化碳和甲烷通量。第二，该项目将调查浮游植物的特性，赋予跨时间尺度的持久性，并将测试的假设，赋予持久性响应短期，随机干扰，如休眠或替代代谢策略的特性将被招募到社区超过几十年的时间尺度。假设将在实验室微观生态系统，户外中生态系统，并使用现代和古湖沼学的方法在五个湖泊的营养梯度跨尺度进行测试。实验围隔生态系统，高频传感器阵列和显微镜设施将被整合到本科湖沼学，藻类学和生态系统生态学课程，旨在培养学生团队科学，实验设计和生态理论。该项目由环境生物学部的人口和社区生态学集群和生态系统科学集群以及刺激竞争研究的既定计划（EPSCoR）共同资助。该奖项反映了NSF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。