Collaborative Research: Quantifying the amount and functional significance of long-term stored-water in trees

准确模拟自然和人为改变的生态系统中的水储存和通量对于在当前和预测的未来气候下管理全球水资源至关重要。准确建模的一个重要步骤是确定树木储存了多少水，以及储存的水量如何随时间和树木器官而变化。 另一个重要的步骤是确定储存的水和储存的水的变化如何影响单个树木和更大的生态系统的生理行为。该项目的研究人员将测量树木不同器官中储存的水量，确定水在这些器官中停留的时间，并评估长期储存的水如何影响整棵树的用水。收集的数据将揭示有关树木如何储存和管理水的新信息，这将最终允许预测树木在当前和未来气候下的水储存和水在生态系统中的运动。爱达荷州的研究地点广泛代表了山间西部的许多景观。这项研究的结果将与斯内克河平原地区的当地社区分享，活动将涉及太平洋西北部部落学院的学生和教职员工。然而，树木中储存了大量的水，水在树木中的停留时间从几天到几个月不等。树木和更广泛的生态系统中储存的水的总量，水在植物中停留的时间，以及树木储水的生态水文影响仍然没有完全了解。描述树木蓄水的持续时间及其对生态水文的影响是改进水文模型的关键。 本研究收集的数据将用于检验以下假设：（1）水分在树木中储存了许多天，停留时间的差异与特定物种和大小的边材结构和水分管理策略相关;（2）储存的水分将缓冲水分运输的下降，因为土壤水分的可用性下降，在每日和季节的时间尺度;（3）在模拟的情景中，由于气候变化，水分储存和运输缓冲策略的物种间差异将转化为全树水分平衡和通量的差异响应。这项工作结合了稳定同位素示踪剂（氘）、气体交换和水力功能性状数据，这些数据是通过基于过程和性状的建模在实地收集的，以确定水在树木器官中的停留时间，树木如何管理器官之间的水储存和运输，以及水储存如何调节整个-该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的知识产权评估的支持。优点和更广泛的影响审查标准。

Accurate modeling of water storage and fluxes in both natural and human-altered ecosystems is critical to managing global water resources under current-day and projected future climates. One important step towards accurate modeling involves determining how much water trees store, and how the amount of stored water varies through time and within tree organs. Another important step involves determining how stored water, and variations in stored water, affect the physiological behavior of individual trees and larger ecosystems. The investigators in this project will measure the amount of water stored in different organs of trees, determine how long water resides in these organs, and evaluate how long-term stored water affects whole-tree water use. The data collected will reveal novel information about how trees store and manage water, which will ultimately allow prediction of tree water storage and water movement through ecosystems in current and future climates. The study site in Idaho broadly represents many landscapes across the Intermountain West. Results from this study will be shared with local communities in the Snake River Plain region, and activities will involve students and faculty members from Tribal Colleges in the Pacific Northwest.Most models assume steady-state water flow through the soil-plant-atmosphere continuum. However, there is substantial storage of water in trees, and the residence times of water inside trees ranges from days to months. The total amount of stored water in trees and broader ecosystems, how long water resides in plants, and the ecohydrological implications of tree water storage are still not completely understood. Characterizing the duration of water storage and its impacts on tree ecohydrology are critical for improving hydrological models. The data collected in this study will be used to test the hypotheses that: (1) Water is stored in trees for many days, with differences in residence time correlating to species- and size-specific sapwood architecture and water-management strategies; (2) Stored water will buffer declines in water transport as soil moisture availability declines, at daily and seasonal timescales; (3) Inter-species differences in water storage and transport-buffering strategies will translate to differential responses in whole-tree water balance and fluxes due to changing climate in modeled scenarios. The work combines stable isotope tracers (deuterium), gas exchange, and hydraulic functional trait data collected in the field with process- and trait-based modeling to determine residence times of water in tree organs, how trees manage water storage and transport among organs, and how water storage regulates whole-tree water relations at hourly to monthly timescales.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.