云南和东南亚三种松树径向生长的气候敏感性研究

Global climate change may have profound effects on the forest structure, composition and productivity of terrestrial ecosystems. A regional arid trend was detected in southwestern China and some regions of Southeast Asia during the past decades. This project will focus on three widely distributed Pinus species (Pinus yunanensis, Pinus kesiya, Pinus merkusii) in the Southeast Asia. We will establish tree-ring networks of the three study species, covering their natural distribution ranges. By combining the techniques of dendrochronology, comparative wood anatomy and stable isotopes, we will measure tree-ring width, intra-annual density fluctuations (IADFs), wood anatomical characters, and stable carbon and oxygen isotopes of wood celluloses. We will analyze growth changes over the past hundred years of three study species along their distribution ranges and altitudinal gradients. Climatic sensitivity and resilience of tree growths of these pine species will be evaluated through point-year analysis. We will discuss long-term trends of intrinsic water-use efficiency (iWUE) and their regional patterns of three pine species. The project will contribute to our understanding about the adaptability of tropical and subtropical coniferous forest ecosystems in Southeast Asia. This study will also provide basic references for sustainable managements of tropical and subtropical coniferous forest resources for this region.

全球气候变化对陆地森林生态系统的结构、组成、生产力等可能产生深远的影响。近年来，我国西南和东南亚部分地区气候变化呈现干旱化趋势。本项目以东南亚热带和亚热带广泛分布的云南松、卡西亚松、南亚松为研究对象，通过在它们的自然分布区域网格式的采样，构建三种松树区域性树木年轮样点网络。结合树木年代学、木材解剖学、稳定性同位素等技术，测定树木年轮宽度、年内密度波动（IADFs）、极端年份木质部解剖、稳定性碳氧同位素等指标，分析不同地域（海拔）分布的三种松树近百年来径向生长的动态历史，找出限制树木生长的关键气候因子；比较三种松树生长对极端气候事件（如干旱）的敏感性和恢复能力；探讨东南亚松属树种长期水分利用效率的变化趋势及其区域特征。有助于深入认识东南亚热带和亚热带地区重要的针叶林生态系统对全球气候变化的适应能力，为制定热带和亚热带地区针叶林资源的可持续管理措施提供理论依据。

本项目以东南亚热带和亚热带广泛分布的云南松、卡西亚松、南亚松为研究对象，通过在它们的自然分布区域网格式的采样，构建三种松树区域性树木年轮样点网络。结合树木年代学、木材解剖学、稳定性同位素等技术，测定树木年轮宽度、年内密度波动、极端年份木质部解剖、稳定性碳氧同位素等指标，分析不同地域（海拔）分布的三种松树近百年来径向生长的动态历史，找出限制树木生长的关键气候因子；比较三种松树生长对极端气候事件（如干旱）的敏感性和恢复能力。项目组完成了西南和东南亚75个松树样点树木年轮采样，并测量了所有样点树木年轮宽度，分析了松树径向生长对气候因子响应的时空格局，构建了8个样点树轮氧同位素（delta18O）序列，分析了树轮早晚材delta18O与气候因子的关系，分析了泰国东北部南亚松长期生长速率及其驱动因子，分析了云南松和思茅松径向生长对短期和长期气候变化的响应特征。项目资助发表论文27篇，其中SCI论文22篇，第一标注SCI论文8篇，培养研究生硕士研究生3名，博士研究生2名。总体上项目取得良好进展，系统阐明了西南和东南亚松属树木径向生长对气候变化响应的时空格局,为热带亚热带暖温性针叶林生态系统的可持续管理提供科学依据。