Climate response of tree growth in Ethiopia along an altitudinal transect and implications on local climate and regional atmospheric circulation dynamics

埃塞俄比亚沿海拔样线树木生长的气候响应及其对当地气候和区域大气环流动态的影响

• 批准号: 42082865
• 负责人: Professor Dr. Achim Bräuning
• 金额: --
• 依托单位: Institut für Geographie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/42082865?language=en
• 关键词: Climate; response; tree; growth; Ethiopia

With the following extension proposal we intend to finalize ongoing studies on the seasonal growth dynamics of native and exotic tree species in the tropical mountain forest of Munessa, Ethiopia. High-resolution dendrometer measurements of stem diameter variations indicated different growth dynamics of evergreen conifer species (Pinus radiata, Podocarpus falcatus) und evergreen and deciduous broadleved tree species (Prunus africana, Celtis africana), respectively. Trees released from competition showed a strong stimulation of stem growth. The knowledge about seasonal wood formation and growth dynamics form the basis for the interpretation of long tree-ring series of ring width and latewood density and of the analysis of annual variations of stable isotopes of 13C and 18O in wood cellulose. Chronologies of stable isotopes of ca. 400 year-old Podocarpus-trees shall be used for the reconstruction of past variations of precipitation. In combination with an extensive tree-ring network from Asia, they shall further be used to analyse variations in the variability of the summer monsoon variability over the Indian Ocean. Furthermore, stable 13C analyses shall provide information on the physiological reaction of the studied tree species (changes of the ‚water use efficiency‘) on extreme drought events, which provides important information for the development of sustainable forest management options under climate change scenarious of increased rainfall variability.

通过以下扩展建议，我们打算在埃塞俄比亚穆纳萨（Munessa）的热带山区森林中对正在进行的有关本地和外来树种的季节性生长动态进行最终研究。茎直径变化的高分辨率树状测量表测量表明，常绿针叶树（Pinus radiata，podocarpus falcatus）和常绿植物和落叶性的发质树种（分别是非洲李子，celtis Africana）的不同生长动力学。竞争中释放的树木对茎生长进行了强烈的模拟。关于季节性木材形成和生长动力学的知识构成了解释环形宽度和晚木密度的长树环系列的基础，以及分析木纤维素中13C和18O的年度变化。 CA的稳定同位素的年表。 400年历史的Podocarpus-Trees应用于重建过去的降水变化。结合亚洲的广泛树环网，应进一步用于分析印度洋夏季季风可变性的变化。此外，稳定的13C分析应提供有关极端干旱事件的Studiod树种物种物理反应的信息，该物种（“用水效率”的变化）为在降雨量变化增加的气候变化情况下提供了重要的信息，以开发可持续森林管理方案。