Collaborative Research: MRA: Dew impacts on ecosystem carbon, energy and water fluxes at continental scale - a synthesis across NEON sites

合作研究：MRA：露水对大陆尺度生态系统碳、能量和水通量的影响 - 跨 NEON 站点的综合

• 批准号: 2307258
• 负责人: Cynthia Gerlein-Safdi
• 金额: $ 56.86万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2307258&HistoricalAwards=false
• 关键词: Collaborative; Research; MRA; Dew; impacts

The processes that control carbon and water flows through vegetation are critical land surface feedbacks on a changing climate. While often overlooked, dew formation can generate up to a 25% reduction in the transpiration flux and may improve plant tolerance of drought or heat stress in xeric systems or during dry periods in mesic systems. Furthermore, dew affects the uptake and exchange of gases across the stomata potentially limiting carbon gain, influences plant susceptibility to some pathogen infections, and supports epiphyte communities. Placing a constraint on the importance of dew to these ecosystem processes is critical since larger, but less frequent, rain events and drier air are expected under warming and may generate broad declines in dew inputs. This project will provide the first comprehensive, macroscale assessment of dew impacts on carbon, energy, and water fluxes across xeric to hydric ecosystems. It will generate a new module for dew implementation in land surface models, enabling further investigations of the impacts of dew in research areas ranging from weather forecasting to microbiology. The project will support the development of a new field-based study abroad program on climate and ecosystem resilience in Puerto Rico where students will participate in fieldwork at NEON sites and take part in workshops and discussions with local scientists. The project will support up to 36 undergraduate students for this, who will be recruited primarily from a minority-serving institution. The project will also support an early career female faculty member as PI, train three PhD students and eight high school students. The formation of dew is a ubiquitous phenomenon that can be an almost daily occurrence in some ecosystems. Dew has a measurable impact on carbon and water fluxes by suppressing transpiration, reducing carbon exchange, and impacting the temperature, albedo, and local vapor pressure deficit (VPD) of the canopy. However, previous work has largely focused on discrete campaigns in arid environments at the leaf or plant level. Here, the first standardized continuous canopy-scale measurement of dew will be generated using infrared radiometry, canopy water content estimates from GPS receivers, and leaf wetness sensors across a hydric to xeric gradient encompassed by the NEON network. The observations will be used for the direct assessment of dew impacts on ecosystem fluxes and for the development and implementation of an ecosystem model that accounts for the effects of dew on surface soil moisture, foliar water uptake, and energy balance. This project will provide fundamental insights into dew impacts on ecosystem processes and a critical constraint on how dew reduction associated with rising temperatures and VPD may exacerbate ecosystem water stress.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.

控制碳和水流过植被的过程是气候变化的关键土地表面反馈。虽然经常被忽略，但露水形成可以使蒸腾通量降低25％，并可以提高Xeric系统中的植物耐受性或热应激的耐受性，或者在中间系统中的干燥时期内。此外，露水会影响气（可能限制碳增长）的气体的吸收和交换，影响植物对某些病原体感染的敏感性，并支持附生植物群落。对露水对这些生态系统过程的重要性构成限制至关重要，因为在变暖下预计较大但频繁的降雨事件和干燥的空气较小，并且可能会在露水输入中产生巨大的下降。该项目将对Xeric到Hydric生态系统的露水对碳，能源和水通量的影响进行首次全面的宏观评估。它将在陆地表面模型中生成一个新的模块，以进一步研究露水对从天气预测到微生物学等研究领域的影响。该项目将支持在波多黎各的气候和生态系统韧性的新基于现场的留学计划，学生将参加霓虹灯地点的野外工作，并与当地科学家参加研讨会和讨论。该项目将为这一点支持多达36名本科生，他们将主要是从少数派服务机构招募的。该项目还将为PI，三名博士生和八名高中生培训早期职业女教师。露水的形成是一种普遍存在的现象，在某些生态系统中几乎每天都会发生。露水通过抑制蒸腾，减少碳交换以及影响冠层的温度，反照率和局部蒸气压力（VPD），对碳和水通量产生了可测量的影响。但是，以前的工作主要集中在叶子或植物水平的干旱环境中的离散运动。在这里，将使用红外辐射测定法，GPS接收器的冠层水含量估计以及横跨Hydric的叶片湿度传感器来生成第一个标准化的连续冠层尺度测量，并将生成neon Network包含的Xeric梯度的叶片湿度传感器。该观察结果将用于直接评估露水对生态系统通量的影响，以及开发和实施生态系统模型，该模型解释了露珠对表面土壤水分，叶面水吸收和能量平衡的影响。该项目将提供对露头对生态系统过程的影响的基本见解，以及对与温度升高和VPD降低相关的降低的关键限制，可能会加剧生态系统水压力。该奖项反映了NSF的法定任务，并通过使用基金会的知识优点和广泛影响来评估来表现出值得通过评估来进行评估。