A rapid Assessment of Post-fire Changes in Biophysical Variables, Carbon Stocks, and Soil Microbial Processes in the Tallest Angiosperm Forest

最高被子植物森林火灾后生物物理变量、碳储量和土壤微生物过程变化的快速评估

• 批准号: 1010769
• 负责人: George Koch
• 金额: $ 7.67万
• 依托单位: Northern Arizona University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1010769&HistoricalAwards=false
• 关键词: rapid; Assessment; Post; fire; Changes

George W. Koch, IOS- 1010769, A rapid assessment of post-fire changes in biophysical variables, carbon stocks, and soil microbial processes in the tallest angiosperm forest. The project examines ecological impacts of the February 2009 fire in the tallest broad-leaf forest on Earth, the Wallaby Creek watershed in Victoria, Australia dominated by Eucalyptus regnans (?Mountain Ash?). Mountain Ash is among the fastest growing trees, and its forests are recognized for their high carbon sequestration potential, yet the prevalence of fires in eucalypt forests raises questions of the permanence of that carbon. The investigators have studied this forest since 2005 and have extensive information on pre-fire conditions, including highly accurate estimates of the mass of individual trees. This follow-up study assesses changes in carbon stocks of soils and trees killed in the fire and samples the crowns of dead trees to test fundamental ideas about height-related variation in wood anatomical and chemical properties. Samples of soils and trees collected from burned and unburned stands, and measurements of dimensions of trees studied prior to the fire, will be used to estimate changes in carbon stocks. Wood samples collected from different heights within the crowns of dead trees will be analyzed in the laboratory to test theories about the optimal design of the dimensions of the water-conducting cells in extremely tall trees. Analysis of the chemical composition (the relative abundance of two stable isotopes of carbon) of wood samples will be used to understand variation in long-term, integrated water stress. The study will produce new understanding of the constraints on tree height and size growth and of the role of fire in the forest carbon cycle, an issue of increasing importance as fire frequency and severity increases with climate change in some regions. The study will involve U.S. students (undergraduate and graduate), postdoctoral associates, and faculty who will collaborate with Australian technical assistants and university researchers.

乔治W. Koch，IOS- 1010769，火灾后生物物理变量，碳储量和最高被子植物森林土壤微生物过程变化的快速评估。 该项目研究了2009年2月火灾对地球上最高的阔叶林，澳大利亚维多利亚的瓦拉比溪流域的生态影响，该流域主要由桉树（？山灰？）。山灰是生长最快的树木之一，其森林因其高固碳潜力而被公认，但森林火灾的普遍存在引发了碳的持久性问题。自2005年以来，调查人员一直在研究这片森林，并掌握了大量关于火灾前状况的信息，包括对每棵树质量的高度准确估计。 这项后续研究评估了火灾中死亡的土壤和树木的碳储量变化，并对死亡树木的树冠进行取样，以测试木材解剖学和化学性质与高度相关变化的基本观点。从燃烧和未燃烧的森林中收集的土壤和树木样本，以及火灾前研究的树木尺寸的测量，将用于估计碳储存的变化。从死树树冠内不同高度收集的木材样本将在实验室中进行分析，以测试关于极高树木中导水细胞尺寸的最佳设计理论。木材样品的化学成分分析（两种稳定碳同位素的相对丰度）将用于了解长期综合水分胁迫的变化。这项研究将使人们对树木高度和大小生长的制约因素以及火灾在森林碳循环中的作用有新的认识，随着一些地区气候变化，火灾频率和严重程度增加，这一问题越来越重要。这项研究将涉及美国学生（本科生和研究生），博士后研究员和教师，他们将与澳大利亚技术助理和大学研究人员合作。