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

合作研究：量化树木长期储存水的数量和功能意义

• 批准号: 2227684
• 负责人: Ryan Emanuel
• 金额: $ 34.32万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2024-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2227684&HistoricalAwards=false
• 关键词: Collaborative; Research; Quantifying; amount; functional

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.

自然和人类改变的生态系统中的储水和通量的准确建模对于在当今和预计未来的气候下管理全球水资源至关重要。迈向准确建模的重要一步是确定水树存储了多少，以及储存的水量如何随着时间的推移和树器官内部而变化。 另一个重要的步骤涉及确定储存水的生理行为和较大的生态系统的生理行为。该项目中的研究人员将测量存储在不同树木器官中的水量，确定这些器官中的水居住多长时间，并评估长期储存的水如何影响全树的用水。收集的数据将揭示有关树木如何存储和管理水的新信息，这最终将允许在当前和未来的气候下通过生态系统进行树木储藏和水的运动。爱达荷州的研究地点广泛地代表了西部山区的许多景观。这项研究的结果将与蛇河平原地区的当地社区共享，活动将涉及西北太平洋部落学院的学生和教职员工。大多数模型假设稳态的水流流经土壤 - 植物 - 大气的连续性。但是，树木中有大量的水储存，树木内的水的住宿时间范围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总量，植物中的水居住多长时间以及树木储存的生态水文含义仍未完全了解。表征储水持续时间及其对树生态水文的影响对于改善水文模型至关重要。 本研究中收集的数据将用于检验：（1）水在树木中储存多天，而停留时间的差异与物种和特异性的Sapwood建筑和水管理策略相关； （2）随着每日和季节性时间标准的土壤水分的可利用率下降，储存的水将在水运输中减少； （3）由于在建模场景中气候变化而导致的全树水平平衡和通量的差异反应中，水存储和运输策略的种间差异将转化为差异反应。这项工作结合了稳定的同位素示踪剂（氘），气体交换以及在现场收集的水力功能性状数据与基于过程和特征的建模，以确定树木器官中的水的停留时间，树木的水库存储和器官之间的运输方式以及水存储如何在每小时至每月的宣传中宣布宣传。通过使用基金会的智力优点和更广泛影响的评论标准进行评估。