Collaborative Research: Understanding the impacts of an ongoing megadrought: Synthesizing the role of soil moisture in driving ecosystem fluxes from site to regional scales

合作研究：了解正在进行的特大干旱的影响：综合土壤湿度在驱动生态系统通量从场地到区域尺度方面的作用

• 批准号: 2331163
• 负责人: Mallory Barnes
• 金额: $ 27.08万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-03-01 至 2027-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2331163&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; impacts; ongoing

Drylands in the American West are currently in the grips of a 23-year long ‘megadrought’, constituting the driest period of the last 1,200 years. This megadrought is an ongoing climate crisis that is severely impacting natural ecosystems, managed forests, agricultural systems, and human water resources. Despite such serious consequences, our understanding of the megadrought is quite limited. Specifically, the research community lacks a comprehensive understanding of how the megadrought has impacted soil moisture, particularly the deeper moisture pools that are critical for vegetation health. There is also a limited understanding of how carbon and water cycling have changed over the last 23 years; an important indicator of ecosystem function that mediates global climate feedbacks. This research enhances our ecological understanding of how drylands have been impacted by the megadrought, which sets the stage for a more predictive understanding of future climate change impacts. This knowledge is transferable to other dryland and non-dryland biomes, as such megadroughts are projected to increase in frequency and severity globally in the coming decades. To accomplish these aims, the research combines hundreds of long-running soil moisture depth profiles with remotely-sensed estimates of shallow soil moisture, deep water availability, and groundwater. These data allow us to assess the impacts of the megadrought on plant-available water, and serve as a crucial validation of these remotely-sensed products for drought monitoring. Data from 21 eddy covariance towers are paired with a new gridded dataset of empirically-modeled ecosystem fluxes to uncover the drivers of dryland ecosystem function, and quantify the impact of the megadrought on carbon-water fluxes at high spatial and temporal resolutions. By synthesizing these data sources their unique strengths are leveraged; addressing detailed mechanistic questions with in situ data, and examining broad trends in carbon-water cycling using modeled and remotely-sensed data. This project is jointly funded by Ecosystem Science 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.

美国西部的旱地目前正遭受长达 23 年的“特大干旱”，这是过去 1,200 年来最干旱的时期。这场特大干旱是一场持续的气候危机，严重影响自然生态系统、管理的森林、农业系统、尽管造成了如此严重的后果，但我们对特大干旱的了解还相当有限，研究界对特大干旱如何影响土壤湿度缺乏全面的了解。特别是对植被健康至关重要的更深的水分库，人们对过去 23 年中碳和水循环如何变化的了解也很有限；这项研究增强了我们对生态系统的认识。旱地如何受到特大干旱的影响，这为对未来气候变化影响进行更具预测性的了解奠定了基础，这些知识可以转移到其他旱地和非旱地生物群落，因为预计此类特大干旱的频率和程度都会增加。为了实现这些目标，该研究将数百个长期土壤湿度深度剖面与浅层土壤湿度、深层水可用性和地下水的遥感估计结合起来。这些数据使我们能够评估气候变化的影响。植物可用水的特大干旱，并作为这些用于干旱监测的遥感产品的重要验证，将来自 21 个涡流协方差塔的数据与新的经验模型生态系统通量网格数据集配对，以揭示驱动因素。通过综合这些数据源，利用现场数据解决详细的机制问题，并研究碳的广泛趋势。 -使用建模和遥感数据的水循环该项目由生态系统科学和刺激竞争性研究既定计划 (EPSCoR) 共同资助。该奖项反映了 NSF 的法定使命，并已获得批准。通过使用基金会的智力优点和更广泛的影响审查标准进行评估，认为值得支持。