Collaborative Proposal: Forest carbon-water interactions in relation to the North American Monsoon climate system

合作提案：森林碳-水相互作用与北美季风气候系统的关系

• 批准号: 1754430
• 负责人: Russell Monson
• 金额: $ 89.53万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-15 至 2023-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1754430&HistoricalAwards=false
• 关键词: Collaborative; Proposal; Forest; carbon; water

Regional climate affects the forest growth and water use in the semi-arid western US. These montane forests depend on water from winter snow and summer rain. This water is provided by different climate systems. The North American Monsoon climate system occurs each year across the southwestern US. It delivers summer rain through near-daily thunderstorms that move northward from the Gulf of California. Winter snow comes from longer-term storms that originate above the Pacific Ocean off the coast of California and move eastward. Water from these different climate systems have different chemistry and timing. Using tree rings this research project will provide insights into how forest growth and water use has responded to past climate variation and how variation in one part of the season (e.g., winter or summer) influences forest growth and water use in the following seasons. This region has experienced reduced snow packs, warmer winter temperatures and an increase in droughts. Therefore, it is important to understand how the change in water availability is affecting the growth of these forests. An understanding of how drought controls forest growth is crucial to not only predicting natural resource production, but also predicting and controlling forest fire frequencies. The research will contribute to an exhibit entitled: 'The Fingerprints of Forest Responses to Climate Variation', in The Laboratory of Tree Ring Research and at the Biosphere 2 campus at the University of Arizona. The research will include the training of two post-doctoral fellows and numerous undergraduate students, with an emphasis on recruitment from the large Hispanic and Native American student populations at the University of Arizona. This research will explore whether variation in the amount of summer or winter precipitation over the past fifty years, in any given year, is negatively correlated with the amount of precipitation during the previous winter or the following summer, respectively, and whether those correlated influences have affected forest wood production and water-cycling in predictable ways. Researchers will examine how trees mobilize stored sugar resources to sustain wood production and water cycling during years with extremely low winter or summer rainfall, and the degree to which the use of stored sugars differentially buffers the effects of extreme winter or summer drought. This project will design a new generation of mathematical models to better predict how variation in winter versus summer precipitation influences forest wood production and water use, and whether there are limits to sustaining wood production following multi-year droughts. The research will utilize advanced techniques in the analysis of stable isotopes in the cellulose extracted from individual tree-rings. A major part of the studies will focus on tree rings produced during the 1960's and 1970's, when atomic bomb testing produced an atmospheric spike of radioactive 14C that was subsequently incorporated into trees. The 14C provides a detectable tracer that facilitates determination of the age of stored sugars in trees and the utilization of those tagged sugars in the production of tree rings specifically, and timber generally. New theory will be developed to provide a foundation for understanding and predicting how trees incorporate stable isotopes of carbon and oxygen from the atmosphere into their wood. All data will be deposited in the International Tree Ring Data Bank, which is administered by the US Department of Commerce, National Oceanic and Atmospheric Administration, and which has been used in numerous multi-national collaborations on understanding how climate controls the health and vigor of forest ecosystems.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.

区域气候影响美国西部半干旱地区的森林生长和水资源利用。这些山地森林依靠冬雪和夏雨中的水分生存。这些水由不同的气候系统提供。北美季风气候系统每年发生在美国西南部。它通过从加州湾向北移动的几乎每天都有的雷暴来输送夏季的雨水。冬季降雪来自长期风暴，这些风暴起源于加州海岸附近的太平洋上空，并向东移动。来自这些不同气候系统的水具有不同的化学性质和时间。利用树木年轮，这个研究项目将提供关于森林生长和用水如何对过去的气候变化做出反应以及季节某个部分的变化（例如，冬季或夏季）影响森林生长和随后季节的用水。该地区积雪减少，冬季气温升高，干旱增加。因此，必须了解水供应的变化如何影响这些森林的生长。了解干旱如何控制森林生长不仅对预测自然资源产量至关重要，而且对预测和控制森林火灾频率也至关重要。这项研究将有助于一个展览，题为：“指纹的森林对气候变化的反应”，在树轮研究实验室和生物圈2号校园在亚利桑那大学。该研究将包括培训两名博士后研究员和众多本科生，重点是从亚利桑那大学大量西班牙裔和美洲原住民学生中招募。本研究将探讨在过去的50年中，夏季或冬季降水量的变化是否与前一个冬季或下一个夏季的降水量分别呈负相关，以及这些相关影响是否以可预测的方式影响森林木材生产和水循环。研究人员将研究树木如何调动储存的糖资源，以维持冬季或夏季降雨量极低的年份的木材生产和水循环，以及储存糖的使用差异缓冲极端冬季或夏季干旱影响的程度。 该项目将设计新一代的数学模型，以更好地预测冬季与夏季降水量的变化如何影响森林木材生产和用水，以及在多年干旱后维持木材生产是否存在限制。这项研究将利用先进技术分析从个别树木年轮中提取的纤维素中的稳定同位素。研究的主要部分将集中在20世纪60年代和70年代产生的树木年轮上，当时原子弹试验产生了放射性14 C的大气峰值，随后被纳入树木中。14 C提供了一种可检测的示踪剂，有助于确定树木中储存的糖的年龄，并利用这些标记的糖生产树木年轮，特别是木材。 新的理论将被开发，为理解和预测树木如何将大气中碳和氧的稳定同位素结合到木材中提供基础。 所有数据将存放在国际树木年轮数据库，该数据库由美国商务部、国家海洋和大气管理局管理，它已经被用于许多多-在理解气候如何控制森林生态系统的健康和活力方面的国家合作。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值进行评估来支持和更广泛的影响审查标准。

项目成果

The North American Monsoon buffers forests against the ongoing megadrought in the Southwestern United States

• DOI: 10.1111/gcb.16762
• 发表时间: 2023-06
• 期刊: Global Change Biology
• 影响因子: 11.6
• 作者: B. Strange;R. Monson;P. Szejner;J. Ehleringer;Jia Hu

Leaf isoprene emission as a trait that mediates the growth-defense tradeoff in the face of climate stress

• DOI: 10.1007/s00442-020-04813-7
• 发表时间: 2021-01-08
• 期刊: OECOLOGIA
• 影响因子: 2.7
• 作者: Monson, Russell K.;Weraduwage, Sarathi M.;Sharkey, Thomas D.
• 通讯作者: Sharkey, Thomas D.

Recent increases in drought frequency cause observed multi-year drought legacies in the tree rings of semi-arid forests

• DOI: 10.1007/s00442-019-04550-6
• 发表时间: 2019-11
• 期刊: Oecologia
• 影响因子: 2.7
• 作者: P. Szejner;S. Belmecheri;J. Ehleringer;R. Monson

Climatic and volcanic forcing of tropical belt northern boundary over the past 800 years

• DOI: 10.1038/s41561-018-0242-1
• 发表时间: 2018-10
• 期刊: Nature Geoscience
• 影响因子: 18.3
• 作者: R. Alfaro‐Sánchez;Hanh Nguyen;S. Klesse;A. Hudson;S. Belmecheri;N. Köse;H. Diaz;R. Monson;R. Villalba;V. Trouet

Disentangling seasonal and interannual legacies from inferred patterns of forest water and carbon cycling using tree‐ring stable isotopes

• DOI: 10.1111/gcb.14395
• 发表时间: 2018-08
• 期刊: Global Change Biology
• 影响因子: 11.6
• 作者: P. Szejner;W. Wright;S. Belmecheri;D. Meko;S. Leavitt;J. Ehleringer;R. Monson