江西三清山黄山松树轮早晚材宽度所指示的气候意义

在中国东南湿润季风区，近十几年来采用树轮宽度进行气候变化研究取得了快速的发展。对于气候限制因子不明确的整轮宽度年表，通过把整轮宽度分割为早材宽度和晚材宽度，分别建立早材宽度年表和晚材宽度年表，从中抽取出了可靠的气候信号。但是对于气候限制因子明确的整轮宽度年表，它们的早晚材宽度年表包含怎样的气候信息却没有开展过研究工作。选用对气候响应非常敏感的江西三清山高海拔黄山松树轮样本进行早晚材宽度的气候响应研究，该样本整轮宽度主要受上年4~7月温度的影响。研究发现，该样点黄山松早材和晚材宽度年表在共同可靠时段（1800~2013年）的相关系数为0.67（p<0.01），早材和晚材宽度的主导气候因素与整轮一致，均表现出明显的“滞后效应”。无论是高频信号，还是低频信号，该关系都成立，这一研究工作很好地解释了东南降水丰沛的高海拔地区黄山松整轮宽度年表对气候响应非常敏感的原因所在。研究工作还表明，早晚材宽度年表包含的气候信号是否一致，对采用整轮宽度年表重建气候的质量具有一定的影响。

Climatic Significance of the Earlywood and Latewood Width of Pinus Taiwanesis in Sanqingshan,Jiangxi Province of China

In the southeastern monsoon region of China, climatic studies based on tree-ring width have made great progress during the past decade. In terms of some tree-ring width chronologies without obvious growth limiting factors to meet the requirement for climatic reconstructions, reliable climatic signals have been successfully extracted by splitting tree-ring width into earlywood and latewood width and building corresponding width chronologies. However, how the corresponding earlywood and latewood of tree-ring width with clear limiting climatic factor respond to climate has not been investigated until now. The tree-ring width chronology of high-altitude Pinus taiwanensis was highly sensitive to prior April-July temperature in Sanqingshan, Jiangxi Province of China. In order to investigate the reason of the high sensitivity and the potential of its corresponding earlywood and latewood chronologies for climatic reconstructions, it was split into sub-annual chronologies, that is, the earlywood- and latewood-width chronologies. Both the sub-annual chronologies were found to have the same dominating climatic factor, i.e., prior April-July temperature, as the original chronology. The relationship stood for both high and low frequencies, which clearly explained why the high-latitude tree-ring width chronology was highly sensitive to climate. The study also demonstrated that the reconstruction quality using tree-ring width chronology could be influenced to some extent by whether the corresponding earlywood- and latewood-width chronologies contained similar climatic signals.