毛竹林碳通量对极端干旱的响应机制与模型模拟研究

项目名称： 毛竹林碳通量对极端干旱的响应机制与模型模拟研究

项目编号： No.31500520

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 农业科学

项目作者： 徐小军

作者单位： 浙江农林大学

项目金额： 20万元

中文摘要： 亚热带地区极端干旱发生的频率和强度持续增加，对森林碳平衡的影响越来越受到关注。竹林是中国亚热带地区特殊的森林类型，在区域碳平衡中具有重要地位和作用。极端干旱引起毛竹胸径减小，采伐量减少，显著降低生产力和碳储量，对可持续经营带来巨大威胁。然而，目前极端干旱对毛竹林影响方面的基础研究还相当缺乏，因此开展本研究对降低未来极端干旱对毛竹林灾害风险具有重要意义和价值。本项目以干旱控制试验、通量观测塔、卫星遥感、碳通量模型和统计分析等技术和方法为手段，开展毛竹碳通量对极端干旱的响应机制及其模型模拟研究，探究环境因子交互效应对毛竹碳通量影响，揭示干旱胁迫下水、温和光对毛竹林碳通量的调控规律；验证干旱引起毛竹死亡机制—碳饥饿假说，阐明气孔和非气孔限制对碳饥饿贡献；构建响应机制数学表达式并融入光能利用率模型，定量评价干旱对毛竹林碳通量的影响，为提高毛竹林固碳经营管理水平提供翔实数据、理论依据和技术支撑。

中文关键词： 碳通量；极端干旱；响应机制；遥感定量反演；毛竹林

英文摘要： The frequency and intensity of extreme drought events increases every year in sub-tropical area, which has a significant impact on the forest ecosystem carbon budget. Bamboo forest is one of special forest types and plays an important role in regional carbon balance. Extreme drought caused decreases in diameter at breast height and harvest and reduced production and carbon storage of Moso bamboo forest, which was a threat to sustainable management. Because few of basic research studied on effect of extreme drought on Moso bamboo forest, this study is significant and valuable to reduce damage risk of extreme drought. This program focuses on response mechanisms of Moso bamboo forest carbon fluxes to extreme drought and their model simulation based on control experiment, eddy covariance technique, satellite remote sensing, ecosystem carbon flux model and statistical analysis. The objectives of this program are to reveal regulation rules of water, temperature and light to Moso bamboo carbon flux under drought stress thought analyzing interaction of environmental factors, to verify the death mechanisms due to carbon starvation and discover the roles of stomatal and nonstomatal limitation in carbon starvation, and to build model expression of mechanisms and then couple them with light use efficiency model for quantitatively evaluating the impact of extreme drought on Moso bamboo forest carbon fluxes. Results will provide detailed data, the theoretical basis and technical support for the management of carbon sequestration.

英文关键词： Carbon flux;Extreme drought;Response mechanism;Quantitative remote sensing inversion;Moso bamboo forest