Collaborative Research: MRA: On thin ice- implications of shorter winters for the future of freshwater phytoplankton phenology and function

世界各地的湖泊都面临着迅速变暖的气温和更短的冬季。这些对冬季地表冰的形成和覆盖有影响，并可能影响湖泊藻类的生长及其与其他水生生物的相互作用。越来越多的藻华威胁着水质、饮用水供应和娱乐活动，以及通过食物网的能量流动。在这个项目中，研究人员将通过研究美国的湖泊，从北到南，从冰雪覆盖到冬季无冰，来模拟气候引起的湖泊变化。他们的研究将利用野外观测、实验和高频环境传感器，在全年范围内检查藻类的生长和相互作用，并将采用预测模型来评估气候变化将如何影响湖泊生态系统的结构和功能。通过社区科学、本科生和研究生研究人员的培训以及公众参与，将实现更广泛的影响。劳动力发展计划将为饮用水水库的水处理厂操作员和高中生提供培训。通过让青年和社区科学家参与进来，这些合作伙伴/参与者将接受培训，在各自社区积极担任水质管理人员，使他们能够了解并参与与气候对湖泊生态系统影响有关的研究。为了研究从冰雪覆盖到无冰冬季的转变，本项目的总体目标是评估冰盖变化对藻类的影响。有明确的需要了解变化的冬季条件如何影响藻类，包括季节演替，竞争结果，以及对先前生态系统条件的生态响应强度（生态记忆）。对非夏季藻类组合的研究很少。连接冰下期和无冰期对于理解冬季冰型变化对湖泊生态系统动态的影响至关重要。这一目标将通过三个具体目标来实现：阐明不同湖泊的冬季条件对藻类群落（包括藻华和蓝藻毒素）在冬季相对于夏季的影响。2. 确定之前条件的生态记忆如何影响当前藻类群落的结构和功能。3. 区分当气候变化情景从冰覆盖的湖泊转向没有表面冰形成的未来时，冰盖、水下光线和藻类将如何应对。工作假设是，冬季冰雪覆盖的逐渐减少将极大地塑造湖泊的物理特征，这为藻类物种的相互作用和竞争结果设定了模板。随着湖泊热状态的变化，藻类群落的相互作用和竞争将发生重大变化，这将改变演替和水华模式。这项工作解决了在快速变化的冬季条件下与社区多样性和集会相关的基础生态问题。研究湖泊包括国家生态观测站网络（NEON）内的湖泊。该项目将有助于教育和培训从事区域到大陆尺度生物学基础研究所需的未来科学和技术人员，并将使学习者、教育工作者和管理人员参与区域到大陆尺度的研究和NEON的使用。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。

Lakes around the world face rapidly warming temperatures coupled with shorter winters. These have an impact on surface ice formation and coverage in winter and can impact growth of lake algae and their interactions with other aquatic organisms. Increased algal blooms threaten water quality, drinking water supply, and recreation, as well as energy flow through food webs. In this project, researchers will mimic climate-induced changing lake futures by studying U.S. lakes from north to south, and ranging from ice covered to ice free in winter months. Their research will examine algal growth and interactions on a year-round scale using field observations, experiments and high-frequency environmental sensors, and will employ predictive modeling to assess how changes in climate will affect lake ecosystem structure and function. Broader Impacts will be achieved through the vehicles of community science, training of undergraduate and graduate researchers, and public engagement. Workforce development initiatives will provide training for water treatment plant operators at drinking water reservoirs and high school students. By engaging youth and community scientists, these partners/participants will be trained to actively serve as stewards of water quality in their respective communities, empowering them to be knowledgeable and engaged in research related to climate impacts on lake ecosystems. To study the transition from ice covered to ice free winters, the overall objective of this project is to assess how changing ice cover impacts algae. There is an explicit need to understand how changing winter conditions influence algae, including seasonal succession, competitive outcomes, and the strength of the ecological response to prior ecosystem conditions (ecological memory). Studies on non-summer algal assemblages are rare. Connecting under-ice and ice-free periods is essential for understanding the impact of changing winter ice patterns on lake ecosystem dynamics. This objective will be accomplished via three specific aims: 1. Elucidate how varying winter conditions across a wide range of lakes affect algal communities (including blooms and cyanotoxins) during the winter relative to summer. 2. Determine how the ecological memory of preceding conditions affects current algal community structure and function. 3. Differentiate how ice cover, underwater light, and algae will respond as climate change scenarios shift from ice covered lakes towards a future with no surface ice formation.The working hypothesis is that the gradual loss of winter ice and snow cover will dramatically shape lake physical characteristics, which sets the template for algal species interactions and competitive outcomes. As a lake’s thermal regime shifts, there will be major changes to algal community interactions and competition, which will alter succession and bloom patterns. This work addresses foundational ecological questions related to community diversity and assembly, placed in the context of rapidly changing winter conditions. Research lakes include those within the National Ecological Observatory Network (NEON). This project will contribute to the education and training of the future scientific and technical workforce needed to pursue basic research on regional to continental scale biology, and will engage a diverse community of learners, educators and managers in regional to continental scale research and the use of NEON.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.