Collaborative Research: Advancing a comprehensive model of year-round ecosystem function in seasonally frozen lakes through networked science

冬季是北半球变暖最快的季节。对于世界上数以百万计的季节性冰冻湖泊来说，这种变暖意味着冰层更短、更薄，以及冰上积雪模式的改变。由于冰雪影响湖泊的许多基本物理、化学和生物特性，冬季条件的变化可能会破坏湖泊生态系统及其为人类提供的服务。直到最近，湖泊科学家对冬季的关注相对较少，这意味着我们对冰雪覆盖的湖泊如何工作以及冬季条件如何影响一年中的其他时间知之甚少。这使得科学家们没有准备好预测冬季变化将如何影响湖泊或减轻负面影响。本研究解决了这一“冬季知识缺口”，并对冬季条件如何影响不同类型湖泊的生态种群、群落和食物网进行了预测性理解。除了核心项目组对湖泊进行深入研究外，调查人员还从几十个机构招募研究人员，将采样范围扩大到更多的湖泊。这种“团队科学”方法将培训许多水生科学家掌握专门的冬季采样方法，使其他科学家能够将冬季条件的研究纳入其研究计划。它将建立一个耐寒水生研究人员网络，目标是促进对气候变化下全年生态系统功能的理解。该项目为多名研究生和本科生以及一名博士后研究员提供教育和培训机会。本研究结合了两种方法：1)由项目调查员对12个湖泊的生态过程进行详细的季节性研究；2)通过合作网络对至少60个其他湖泊进行研究。在第一部分工作中，调查人员将重点关注12个水质特征和冬季严酷程度截然不同的湖泊。这些湖泊正在用连续记录温度、光线和氧气的传感器进行监测。研究人员还研究了全年的水、细菌、浮游植物和浮游动物，以确定浮游生物的数量和群落是如何随着不同湖泊类型的季节而进化的。利用稳定同位素和脂肪酸分析，研究人员正在评估食物网结构随季节变化的方式以及有机物的生产和循环。在研究的第二部分，研究人员正在招募一个研究人员网络，从至少另外60个湖泊收集样本。正在对这些合作者进行冬季研究方法方面的培训，并向他们提供取样包和取样说明。他们的样本正在与12个核心湖泊的样本进行分析，以确保结果的兼容性。合作项目和他们的网络之间的合作，允许广泛参与解释数据和测试关于冬季严酷程度如何与水质相互作用以影响湖泊生态的假设。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。

Winter is the fastest warming season in the northern hemisphere. For millions of the world’s seasonally-frozen lakes, this warming means shorter and thinner ice cover and changing patterns of snow accumulation on the ice. Because ice and snow affect many fundamental physical, chemical, and biological properties of lakes, changes in winter conditions can disrupt lake ecosystems and the services they provide to humanity. Until recently, lake scientists paid relatively little attention to winter, meaning we know very little about how lakes work when covered by ice and snow and how winter conditions affect the rest of the year. This leaves scientists ill-prepared to predict how changing winters will impact lakes or to mitigate negative impacts. This study addresses this “winter knowledge gap” and develops a predictive understanding of how winter conditions affect the ecological populations, communities, and food webs of diverse types of lakes. Along with intensive studies of lakes by the core project team, the investigators are also recruiting researchers from dozens of institutions to expand sampling to many additional lakes. This ‘Team Science’ approach will train many aquatic scientists in specialized winter sampling methods, empowering other scientists to include studies of winter conditions in their research programs. It will develop a network of winter-hardy aquatic researchers with the goal of advancing understanding of year-round ecosystem function in the face of climate change. The project provides education and training opportunities for multiple graduate and undergraduate students and a postbaccalaureate researcher.This study combines two approaches: 1) detailed seasonal studies of ecological processes in 12 lakes by the project’s investigators; and 2) research across at least 60 other lakes by a network of collaborators. In the first part of the effort, the investigators are focusing on 12 lakes with contrasting water quality characteristics and winter severity. The lakes are being instrumented with continuously-recording temperature, light, and oxygen sensors. The investigators are also studying water, bacteria, phytoplankton, and zooplankton throughout the year to determine how plankton populations and communities evolve through seasons in different lake types. Using stable isotopes and fatty acid analysis, the investigators are assessing the way food web structure changes across seasons and the production and cycling of organic matter. For the second part of the study, the investigators are recruiting a network of researchers to collect samples from at least another 60 lakes. These collaborators are being trained in winter research methods and are provided with sampling kits and instructions for sample collection. Their samples are being analyzed with samples from the core set of 12 lakes, ensuring compatibility of results. Collaboration between the co-PIs and their network is allowing for broad participation in interpretation of data and testing of hypotheses about the way winter severity interacts with water quality to affect lake ecology.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.