Collaborative Research: Are Amazon forest trees source or sink limited? Mapping hydraulic traits to carbon allocation strategies to decipher forest function during drought

合作研究：亚马逊森林树木的来源或汇是否有限？

基本信息

批准号：
1754803
负责人：
Scott Saleska
金额：
$ 104.94万
依托单位：
University of Arizona
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-15 至 2023-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1754803&HistoricalAwards=false
关键词：
Collaborative Research Amazon forest trees

项目摘要

Understanding how large expanses of tropical forests will respond to climate variation, including increasing frequency of droughts, is important since these forests play a big role in the planet's carbon cycle. This award provides funds to study how the Amazon forest will respond to droughts such as experienced in the recent El Nino. Researchers will examine how individual species capture and use carbon and water, and use that data to understand how biodiversity of species makes the whole forest more resilient to droughts. The results will be integrated to model and predict how differences in forest species composition result in differences in whole-forest responses to drought. This award will evaluate how composition of biological communities influences their overall function and the effects of future changes on entire tropical forests. The project will advance international collaboration and the training of U.S. undergraduates to do research in Brazil. Increased public awareness of these issues will occur through outreach programs at the Biosphere 2, and a Science Festival which facilitates targeted presentations about the Amazon to 100+ middle-high school students/year. The science of plant drought response has largely assumed that environment regulates photosynthetic source of carbon ('C-source regulation'), which is then allocated to growth and other functions according to fixed allometric rules. There is an emerging view, however, that within-plant C-sink processes (growth, storage, and respiration) are directly regulated by the environment and by within-plant feedbacks (the 'C-sink regulation' hypothesis), such that changes in allocation and sink processes are a key mechanism of drought response. Realistically propagating such mechanisms to the ecosystem scale requires accounting for species-specific strategies that vary across the plant economic spectrum. To realistically test this hypothesis, the following challenges will be me through integrating measurements of tree C-source (photosynthesis) and C-sink (growth, storage, respiration) processes across a range of hydraulic traits to identify regulating mechanisms; Upscaling the mechanisms of drought response to the ecosystem level by focusing on distributions of both resources and plant hydraulic traits mapped to the plant economic spectrum; and Observing the ecosystem-scale photosynthetic C source (Gross Ecosystem Productivity, GEP) and water loss by transpiration. This evaluation of the controls on tree C-source and C-sink processes - including the Kok effect, Non-Structural C storage, and plant water relations - will transform our understanding of Amazon forest C dynamics and assessment of the forest's future under climate change.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.

了解大片热带森林将如何应对气候变化（包括干旱频率的增加）非常重要，因为这些森林在地球的碳循环中发挥着重要作用。该奖项提供资金来研究亚马逊森林将如何应对最近厄尔尼诺现象所经历的干旱。研究人员将研究单个物种如何捕获和利用碳和水，并利用这些数据来了解物种的生物多样性如何使整个森林更能抵御干旱。结果将被整合以模拟和预测森林物种组成的差异如何导致整个森林对干旱反应的差异。该奖项将评估生物群落的组成如何影响其整体功能以及未来变化对整个热带森林的影响。该项目将促进国际合作和美国本科生在巴西开展研究的培训。通过生物圈 2 号的外展计划和科学节，将提高公众对这些问题的认识，科学节每年向 100 多名中学生提供有关亚马逊的有针对性的演示。植物干旱响应科学在很大程度上假设环境调节碳的光合来源（“碳源调节”），然后根据固定的异速生长规则将其分配给生长和其他功能。然而，有一种新兴观点认为，植物内碳汇过程（生长、储存和呼吸）直接受到环境和植物内反馈的调节（“碳汇调节”假说），从而改变分配和汇过程是干旱应对的关键机制。实际上，将这种机制传播到生态系统规模需要考虑在植物经济范围内变化的物种特定策略。为了实际检验这一假设，我将面临以下挑战：通过整合树木碳源（光合作用）和碳汇（生长、储存、呼吸）过程的一系列水力特性的测量来确定调节机制；通过关注映射到植物经济谱的资源和植物水力特征的分布，将干旱响应机制升级到生态系统水平；观测生态系统规模的光合碳源（生态系统总生产力，GEP）和蒸腾水分损失。对树木碳源和碳汇过程控制的评估（包括科克效应、非结构性碳储存和植物水关系）将改变我们对亚马逊森林碳动态的理解以及对气候变化下森林未来的评估该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Diverse anthropogenic disturbances shift Amazon forests along a structural spectrum

各种人为干扰使亚马逊森林发生结构变化

DOI：
10.1002/fee.2590
发表时间：
2023-02
期刊：
Frontiers in Ecology and the Environment
影响因子：
10.3
作者：
Smith, Marielle N;Stark, Scott C;Taylor, Tyeen C;Schietti, Juliana;de Almeida, Danilo Roberti;Aragón, Susan;Torralvo, Kelly;Lima, Albertina P;de Oliveira, Gabriel;de Assis, Rafael Leandro;et al
通讯作者：
et al

Calculating Canopy Stomatal Conductance from Eddy Covariance Measurements, in Light of the Energy Budget Closure Problem

根据能源预算闭合问题，根据涡流协方差测量计算冠层气孔导度

DOI：
10.5194/bg-2020-154
发表时间：
2020-05
期刊：
Biogeosciences discussions
影响因子：
0
作者：
Wehr, Richard;Saleska, Scott R.
通讯作者：
Saleska, Scott R.

B24E-02 Photosynthesis and evapotranspiration along central Amazonia during an extreme drought event. AGU Fall 2019 meeting, San Francisco, CA, USA.

B24E-02 极端干旱事件期间亚马逊流域中部的光合作用和蒸散量。

DOI：
发表时间：
2019-12
期刊：
AGU Fall 2019 meeting
影响因子：
0
作者：
De Araujo; A C.
通讯作者：
A C.

Reconciling discrepancies in measurements of vulnerability to xylem embolism with the pneumatic method

使用气动方法协调木质部栓塞脆弱性测量的差异

DOI：
10.1111/nph.18531
发表时间：
2023-01
期刊：
New Phytologist
影响因子：
9.4
作者：
Brum, Mauro;Pereira, Luciano;Ribeiro, Rafael Vasconcelos;Jansen, Steven;Bittencourt, Paulo R.;Oliveira, Rafael S.;Saleska, Scott R.
通讯作者：
Saleska, Scott R.

Hydraulic traits explain differential responses of Amazonian forests to the 2015 El Nino‐induced drought

水力特征解释了亚马逊森林对 2015 年厄尔尼诺现象引起的干旱的不同反应

DOI：
10.1111/nph.15909
发表时间：
2019-05
期刊：
New Phytologist
影响因子：
9.4
作者：
Barros, Fernanda V.;Bittencourt, Paulo R.;Brum, Mauro;Restrepo‐Coupe, Natalia;Pereira, Luciano;Teodoro, Grazielle S.;Saleska, Scott R.;Borma, Laura S.;Christoffersen, Bradley O.;Penha, Deliane;et al
通讯作者：
et al