Tropical Climate Reconstruction with Tree-Ring Chronologies from the Central Amazon and Eastern Highlands of Brazil

利用亚马逊中部和巴西东部高地的树轮年表重建热带气候

• 批准号: 1261431
• 负责人: David Stahle
• 金额: $ 6.5万
• 依托单位: University of Arkansas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1261431&HistoricalAwards=false
• 关键词: Tropical; Climate; Reconstruction; Tree; Ring

This collaborative project will involve the University of Arkansas (David Stahle), the Brazilian National Institute for Amazonian Research/Max Planck Institute (Jochen Schongart), and the Federal University at Lavras, Brazil (Ana Carolina Barbosa). Rigorous dendrochronological methods will be used to train students and faculty at both institutions and to develop several exactly dated, well replicated ring-width chronologies covering the last 300-years in the seasonally flooded bottomland forests of the central Amazon basin and in seasonally dry upland forests of eastern Brazil. Exactly dated tree-ring chronologies provide a vital preindustrial perspective on global warming and have produced the only spatially distributed estimates of past megadroughts and pluvials needed for testing climate model simulations of the dynamics responsible for decadal moisture regimes over North America. The vast majority of tree-ring chronologies available worldwide have been developed from temperate and boreal forests. However, the most biodiverse forest ecosystems in the world, the forests of the Amazon Basin in Brazil, have not produced a single freely available multi-century tree-ring chronology useful for exact dating or climate reconstruction. In the absence of a cold winter dormant season, most tropical tree species do not produce anatomically distinctive annual growth rings and therefore cannot be used for routine dendrochronology. However, strong environmental rhythms do exist in some tropical forests and can induce annual ring formation in a few native species. This includes the profound precipitation seasonality and the prolonged flood pulse of lowland forests in the central Amazon. Preliminary research has proven that annual rings exist in Macrolobium acacifolium in these inundation forests and their potential value for hydroclimatic applications has been demonstrated. Annual rings have also been proven in Cedrella fissilis and C. odorata from seasonally dry upland forests of Brazil and eastern Bolivia, and ring width and oxygen isotope chronologies from both are related to large-scale climate variability. A major impediment to the development of long climate sensitive tree ring chronologies in Amazonia has been the lack of expertise with the rigorous application of dendrochronology, the most accurate and precise dating method in geochronology. The 300-year long master chronologies of tree growth and climate history that will be developed through this project are expected to leverage a wide range of interdisciplinary research, including climate dynamics, isotope paleoclimatology, and forest ecology. Once this research concept is proven, further collaborative investigations are envisioned that involve US and Brazilian scientists, in order to model the climate and stream flow response of the derived chronologies, develop calibrated reconstructions of annual hydroclimatic conditions, and investigate the large scale ocean-atmospheric forcing of moisture regimes over tropical South America.

该合作项目将涉及阿肯色大学（David Stahle），巴西国家亚马逊研究所/马克斯·普朗克研究所（Jochen Schongart）和巴西Lavras的联邦大学（ANA CAROLINA CAROLINA BARBOSA）。 严格的Dendroanological方法将用于培训这两个机构的学生和教职员工，并开发出几个过时的，重复的环形宽度时间表，涵盖了亚马逊中部盆地中部季节性洪水底层森林的最后300年，以及在巴西东部季节性干燥的高地森林中。 确切的日期树环的时间顺序为全球变暖提供了重要的工业前观点，并产生了对过去的大型概念和pluvials的唯一空间分布的估计，用于测试对北美际水分状况的气候模型模拟的气候模型模拟。 温带和北方森林已开发出全球范围内的绝大多数树架年代。 但是，世界上最生物多样性的森林生态系统，即巴西的亚马逊盆地的森林，并未产生单一可免费获得的多世纪树环时间学，可用于精确的约会或气候重建。 在没有寒冷的冬季休眠季节的情况下，大多数热带树种不会产生解剖学上独特的年生长环，因此不能用于常规的树突年代学。 但是，在某些热带森林中确实存在强烈的环境节奏，并且可以在几种本地物种中诱导年度环形成。 这包括亚马逊中部中部降水季节性的季节性深远和低地森林的洪水脉搏。 初步研究已经证明，在这些淹没林中，大量阿基佛菌中存在年度环，并且已经证明了它们对氢化气候应用的潜在价值。 在巴西和玻利维亚东部季节性干燥的高地森林中，塞德雷拉·菲西里斯（Cedrella Fissilis）和odorata的cedrella fissilis和C. odorata也已证明了年度环，并且来自两者的环宽度和氧同位素年代与大规模气候变化有关。 在亚马逊地区长期气候敏感树环的发展的主要障碍是缺乏专业知识，因为树突年代学的严格应用，这是年代学中最准确，最精确的约会方法。 预计将通过该项目开发的300年历史的树木生长和气候历史年代表将利用广泛的跨学科研究，包括气候动力学，同位素古气候学和森林生态学。 一旦证明了这一研究概念，就会设想进一步的合作研究，使我们和巴西科学家涉及，以模拟派生的年表的气候和流动流动响应，并开发了年度水力气候条件的校准重建，并研究大型海洋 - 大型海洋 - 大气强度强迫在热带南部美国的水分强迫。