LTER: MCM6 - The Roles of Legacy and Ecological Connectivity in a Polar Desert Ecosystem

LTER：MCM6 - 极地沙漠生态系统中遗产和生态连通性的作用

• 批准号: 2224760
• 负责人: Michael Gooseff
• 金额: $ 765万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2029-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2224760&HistoricalAwards=false
• 关键词: LTER; MCM6; Roles; Legacy; Ecological

Non-technical AbstractThe McMurdo Dry Valleys LTER seeks to understand how changes in the temporal variability of ecological connectivity interact with existing landscape legacies to alter the structure and functioning of this extreme polar desert ecosystem. This research has broad implications, as it will help us to understand how natural ecosystems respond to ongoing anthropogenic global change. At the same time, this project also serves an important educational and outreach function, providing immersive research and educational experiences to students and artists from diverse backgrounds, and helping to ensure a diverse and well-trained next generation of leaders in polar ecosystem science and stewardship. Ultimately, the results of this project will help us to better understand and prepare for the effects of climate change and develop scientific insights that are relevant far beyond Antarctic ecosystems. The McMurdo Dry Valleys (MDVs) make up an extreme polar desert ecosystem in the largest ice-free region of Antarctica. The organisms in this ecosystem are generally small. Bacteria, microinvertebrates, cyanobacterial mats, and phytoplankton can be found across the streams, soils, glaciers, and ice-covered lakes. These organisms have adapted to the cold and arid conditions that prevail outside of lakes for all but a brief period in the austral summer when the ecosystem is connected by liquid water. In the summer when air temperatures rise barely above freezing, soils warm and glacial meltwater flows through streams into the open moats of lakes. Most biological activity across the landscape occurs in summer. Through the winter, or polar night (6 months of darkness), glaciers, streams, and soil biota are inactive until sufficient light, heat, and liquid water return, while lake communities remain active all year. Over the past 30 years, the MDVs have been disturbed by cooling, heatwaves, floods, rising lake levels, as well as permafrost and lake ice thaw. Considering the clear ecological responses to this variation in physical drivers, and climate models predicting further warming and more precipitation, the MDV ecosystem sits at a threshold between the current extreme cold and dry conditions and an uncertain future. This project seeks to determine how important the legacy of past events and conditions versus current physical and biological interactions shape the current ecosystem. Four hypotheses will be tested, related to 1) whether the status of specific organisms are indicative ecosystem stability, 2) the relationship between legacies of past events to current ecosystem resilience (resistance to big changes), 3) carryover of materials between times of high ecosystem connectivity and activity help to maintain ecosystem stability, and 4) changes in disturbances affect how this ecosystem persists through the annual polar night (i.e., extended period of dark and cold). Technical AbstractIn this iteration of the McMurdo LTER project (MCM6), the project team will test ecological connectivity and stability theory in a system subject to strong physical drivers (geological legacies, extreme seasonality, and contemporary climate change) and driven by microbial organisms. Since microorganisms regulate most of the world’s critical biogeochemical functions, these insights will be relevant far beyond polar ecosystems and will inform understanding and expectations of how natural and managed ecosystems respond to ongoing anthropogenic global change. MCM6 builds on previous foundational research, both in Antarctica and within the LTER network, to consider the temporal aspects of connectivity and how it relates to ecosystem stability. The project will examine how changes in the temporal variability of ecological connectivity interact with the legacies of the existing landscape that have defined habitats and biogeochemical cycling for millennia. The project team hypothesizes that the structure and functioning of the MDV ecosystem is dependent upon legacies and the contemporary frequency, duration, and magnitude of ecological connectivity. This hypothesis will be tested with new and continuing monitoring, experiments, and analyses of long-term datasets to examine: 1) the stability of these ecosystems as reflected by sentinel taxa, 2) the relationship between ecological legacies and ecosystem resilience, 3) the importance of material carryover during periods of low connectivity to maintaining biological activity and community stability, and 4) how changes in disturbance dynamics disrupt ecological cycles through the polar night. Tests of these hypotheses will occur in field and modeling activities using new and long-term datasets already collected. New datasets resulting from field activities will be made freely available via widely-known online databases (MCM LTER and EDI). The project team has also developed six Antarctic Core Ideas that encompass themes from data literacy to polar food webs and form a consistent thread across the education and outreach activities. Building on past success, collaborations will be established with teachers and artists embedded within the science teams, who will work to develop educational modules with science content informed by direct experience and artistic expression. Undergraduate mentoring efforts will incorporate computational methods through a new data-intensive scientific training program for MCM REU students. The project will also establish an Antarctic Research Experience for Community College Students at CU Boulder, to provide an immersive educational and research experience for students from diverse backgrounds in community colleges. MCM LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science and stewardship. Historically underrepresented participation will be expanded at each level of the project. To aid in these efforts, the project has established Education & Outreach and Diversity, Equity, and Inclusion committees to lead, coordinate, support, and integrate these activities through all aspects of MCM6.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.

非技术摘要麦克默多干谷 LTER 旨在了解生态连通性的时间变化如何与现有景观遗产相互作用，从而改变这个极端极地沙漠生态系统的结构和功能。这项研究具有广泛的意义，因为它将帮助我们了解自然生态系统如何应对持续的人为全球变化，同时，该项目还提供重要的教育和功能推广，为来自不同背景的学生和艺术家提供身临其境的研究和教育体验，并帮助确保多样化和良好的环境。训练有素的最终，该项目的结果将帮助我们更好地了解气候变化的影响并为之做好准备，并形成与南极生态系统（MDV）无关的科学见解。 ）在南极洲最大的无冰地区构成了一个极端的极地沙漠生态系统，该生态系统中的生物体通常较小，包括细菌、微型无脊椎动物、蓝细菌垫等。浮游植物遍布溪流、土壤、冰川和冰雪覆盖的湖泊，这些生物已经适应了湖泊以外的寒冷和干旱条件，除了南半球夏季生态系统通过液体连接的短暂时期外。夏季，气温仅升至冰点以上，土壤温暖，冰川融水通过溪流流入开阔的湖泊护城河，大部分生物活动都发生在冬季或极夜。 （6 个月的黑暗），冰川、溪流和土壤生物群在足够的光、热和液态水返回之前处于不活跃状态，而湖泊群落全年保持活跃。在过去 30 年中，MDV 一直受到降温和热浪的干扰。考虑到对这种物理驱动因素变化的明显生态反应，以及预测进一步变暖和更多降水的气候模型，MDV生态系统处于当前极端情况之间的阈值。该项目旨在确定过去的事件和条件与当前的物理和生物相互作用对当前生态系统的影响有多重要，这些假设与 1）特定生物体的状态有关。是指示性生态系统稳定性，2）过去事件的影响与当前生态系统恢复力（对大变化的抵抗力）之间的关系，3）生态系统高连通性和活动期间物质的遗留有助于维持生态系统稳定性，4）干扰的变化影响这个生态系统的持续存在技术摘要在麦克默多 LTER 项目 (MCM6) 的这一迭代中，项目团队将在受强大物理驱动因素（地质遗产）影响的系统中测试生态连通性和稳定性理论。 、极端季节性和当代气候变化）并由微生物驱动，由于微生物调节世界上大多数关键的生物地球化学功能，这些见解将远远超出极地生态系统的范围，并将有助于人们了解和期望自然的程度。 MCM6 建立在先前在南极洲和 LTER 网络内的基础研究的基础上，考虑连通性的时间方面及其与生态系统稳定性的关系。生态连通性的可变性与现有景观的遗产相互作用，这些景观定义了数千年来的栖息地和生物地球化学循环。项目团队一直认为，MDV 生态系统的结构和功能取决于遗产和当代的频率、持续时间和影响。该假设将通过新的、持续的监测、实验和长期数据集分析来检验：1）哨兵类群所反映的这些生态系统的稳定性，2）生态遗产与生态系统之间的关系复原力，3）低连接时期物质残留对维持生物活动和群落稳定性的重要性，以及4）扰动动态的变化如何扰乱极夜期间的生态循环这些假设的测试将在现场和建模活动中进行。新的和长期的实地活动产生的新数据集将通过众所周知的在线数据库（MCM LTER 和 EDI）免费提供。该项目团队还制定了六个南极核心想法，涵盖从数据素养到极地食物网和形态的主题。在过去的成功基础上，将与科学团队中的教师和艺术家建立合作，他们将致力于开发包含直接经验和艺术表达的科学内容的教育模块。将结合计算方法通过为 MCM REU 学生提供新的数据密集型科学培训计划，该项目还将为 CU Boulder 的社区学院学生建立南极研究体验，为社区学院来自不同背景的学生提供身临其境的教育和研究体验。将继续其培训和指导学生、博士后和早期职业科学家的使命，作为极地生态系统科学和管理领域的下一代领导者，历史上代表性不足的参与将在该项目的各个层面得到扩大。这些努力，该项目建立了教育和外展以及多元化、公平和包容性委员会来领导、协调、支持和整合这些活动，这反映在 MCM6 的各个方面。该奖项的法定使命，并通过使用评估被认为值得支持基金会的智力价值和更广泛的影响审查标准。