Temperature responses of leaf dark respiration and their implications for tropical forest carbon balance

叶片暗呼吸的温度响应及其对热带森林碳平衡的影响

• 批准号: 1051789
• 负责人: Jeremy Lichstein
• 金额: $ 44.47万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-15 至 2016-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1051789&HistoricalAwards=false
• 关键词: Temperature; responses; leaf; dark; respiration

Dark respiration by plants (i.e., energy consumption for metabolism) is estimated to consume 30-80% of daily photosynthetic carbon uptake in forest ecosystems and is predicted to increase with warming. This project will study how climate warming affects dark respiration and photosynthetic carbon uptake by leaves in the upper tropical forest canopy, using a canopy crane managed by the Smithsonian Tropical Research Institute in Panama. The ultimate goal of this project is to advance a process-based model of forest carbon dynamics and its response to climate changes. The investigators will characterize the relationship between dark respiration and temperature for various species with different ecological characteristics, such as evergreen trees, deciduous trees and woody vines, using in-situ measurements under natural environmental variation as well as measurements under controlled temperature settings in the lab. Experimental manipulation of long-term temperature regimes for canopy leaves and seedlings will be used to test whether they can acclimate or ameliorate the negative impact of warmer temperature on their carbon balance and growth rates. Thus, the results of this project will fill a critical gap in empirical knowledge of dark respiration characteristics of plants in tropical forests, which are responsible for more than one third of the global photosynthetic carbon uptake. The researchers will apply the empirical data to a sophisticated computer-simulation model of climate-vegetation feedbacks, and evaluate how species diversity and associated functional diversity in the tropical forests respond to changing climate and atmospheric carbon dioxide concentration. The project will add significantly to ongoing efforts to develop comprehensive academic programs that address climate change and sustainability. The project will provide research and participatory learning opportunities to undergraduate and graduate students. Courses will be enhanced through ecosystem modeling exercises that illustrate climate-vegetation feedbacks, as well as online activities in which students will learn about the ongoing projects and experiments and engage in blog-based discussions.

据估计，植物的暗呼吸（即代谢能源消耗）在森林生态系统中消耗30-80％的每日光合碳吸收，预计随着变暖而增加。该项目将使用由巴拿马史密森尼热带研究所管理的顶篷起重机研究，研究气候变暖如何影响热带森林冠层的叶子的黑暗呼吸和光合碳吸收。该项目的最终目标是推进基于过程的森林碳动态模型及其对气候变化的反应。研究人员将使用不同生态特征的各种物种（例如常绿树，落叶树和木质藤蔓）来表征黑暗呼吸与温度之间的关系，在自然环境变化下，以及在实验室中受控温度设置下进行测量。对冠层叶子和幼苗的长期温度状态的实验性操纵将用于测试它们是否可以适应或改善温度较高温度对碳平衡和生长速率的负面影响。因此，该项目的结果将填补热带森林中植物的黑暗呼吸特征的经验知识的关键空白，这些植物是造成全球光合碳吸收的三分之一以上的原因。研究人员将将经验数据应用于气候蔬菜反馈的复杂计算机模拟模型，并评估热带森林中物种多样性和相关功能多样性如何响应不断变化的气候和大气二氧化碳浓度。该项目将极大地增加正在进行的努力，以制定解决气候变化和可持续性的全面学术计划。该项目将为本科和研究生提供研究和参与性学习机会。将通过生态系统建模练习来增强课程，这些练习说明气候蔬菜反馈，以及在线活动，学生将了解正在进行的项目和实验并从事基于博客的讨论。