Tree-Ring Based Reconstruction of Drought over the Past 500-1000 Years in the Eastern United States

基于树轮的美国东部过去 500-1000 年干旱重建

• 批准号: 0116831
• 负责人: Edward Cook
• 金额: $ 28.36万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-15 至 2005-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0116831&HistoricalAwards=false
• 关键词: Tree; Ring; Based; Reconstruction; Drought

This award will support research to reconstruct the drought history of the eastern United States over the last 500-1,000 years using the analysis of tree-rings from two species of long-lived conifers; the eastern red cedar (Juniperus virginiana) and the northern white cedar (Thuja occidentalis). This data will greatly improve estimates of the full range of drought variability across the United States. The widespread discovery of ancient forests of these tree species living or preserved on steep cliff faces in the northeast will enable the development of tree-ring chronologies covering the past 1,000 years from living trees and well-preserved fossil wood. Eastern red and northern white cedar may represent the only widely distributed species that are available for developing a network of such long drought-sensitive tree-ring chronologies in the eastern United States. The dendroclimatic potential of black gum (Nyssa sylvatica) growing in wetlands and swamps in the northeastern United States will also be examined. This is one of the longest-lived hardwoods in the world with a documented age of 500-700 years. Preliminary analyses indicate that this species produces cross-datable tree rings that correlate significantly with summer temperatures. A small network of black gum chronologies will be developed to determine the feasibility of using this species to reconstruct past summer temperatures in excess of 500 years before the present.

该奖项将支持通过对两种长寿针叶树的年轮进行分析来重建美国东部过去 500-1,000 年干旱历史的研究；东部红雪松（Juniperus virginiana）和北部白雪松（Thuja occidentalis）。这些数据将极大地改进对美国各地干旱变化范围的估计。在东北部陡峭的悬崖面上生活或保存着这些树种的古老森林的广泛发现，将有助于从活树和保存完好的木化石中开发出涵盖过去 1000 年的树轮年表。东部红雪松和北部白雪松可能是唯一可在美国东部形成如此长的干旱敏感树轮年表网络的广泛分布的物种。生长在美国东北部湿地和沼泽中的黑胶树（Nyssa sylvatica）的树木气候潜力也将受到检查。这是世界上最长寿的硬木之一，有记录的树龄为 500-700 年。初步分析表明，该物种产生的树木年轮与夏季气温显着相关。将开发一个小型的黑胶年代学网络，以确定利用该物种重建 500 多年以前夏季温度的可行性。