摘要
建立了秦岭东缘高海拔华山松树轮宽度年表,年表的可靠时段是从1911年到2005年(子样本强度大于0.8),基于此年表重建了秦岭东缘过去百年来冬半年(上年12月到当年4月)温度变化,重建方程的方差解释量为51%。重建序列有3个温暖时段:1938～1944年,1958～1967年和1998～2005年;两个冷时段:1945～1957年和1968～1976年。自1968年以来,温度开始上升,但温度变化幅度未表现出明显异常。秦岭东缘和华北、华中及华东邻近,本文重建的温度序列与这3个区域的温度变化在低温、高温时段对应一致,而且相关显著,都表现出自1970s以来的升温趋势。表明在秦岭东缘采用高海拔华山松重建冬半年温度具有很大的潜力。
global warming has proven true, studies have also indicated that there are large differences in temperature change in different regions. As a result,efforts to understand historic temperature change over different regions of China are in need. In this study,we chose the Eastern Qinling Mountains as the research region,as it is a transitional region between subtropical and temperate climate. Previous tree-ring research showed that there is complex relationship between tree growth and climate factors. Therefore,we collected Pinus armandii Franch and Pinus tabulaeformis at different elevations from 1200m to 2200m above sea level（ a. s. 1. ）. The most significant relationship is found between high-elevation Pinus armandii Franch tree growth and winter-half year temperature （previous December to current April）. The Pinus armandii Franch tree-ring width chronology used in this study was from the highest among our sampling sites,with an elevation range between 2100m and 2180m a. s. 1. The reliable period is from 1911 to 2005 （subsample signal strength 〉 0. 8）. The chronology is correlated positively with temperature from previous December to current April, with statistically significant correlations （ at 0.05 level） found in January （ r = 0. 30）, February （ r = 0.58） , March （ r = 0.30 ） , April （ r = 0. 42 ） and winter-half year mean temperature （ r = 0. 71 ）. Based on these relationships, the winter-half year mean temperature in the sampling region was reconstructed using the function T12.4 =2. 327 × RW ＋2. 186（N =48,R =0.71 ,R^2 =0.51 ,R^2adj =0.50,F（1,46） =47.86,p 〈0. 001） ,where T12.4 is the winter-half year mean temperature and RW is the ring-width standard chronology. The reconstructed and actual temperature series agree well at both high-or low-frequency bands. Both sign test and product mean test show that the reconstruction is significant at 0.01 level. It is shown that there are 3 warm spells,i, e.,1938 - 1944, 1958 - 1967 and 1998 - 2005 and 2 cold stages, i. e., 1945 - 1957 and 1968 - 1976 during the reconstructed time period. An increasing temperature trend is clear since 1968 ,but it remains in natural ranges until now. The reconstructed winter-half year temperature series in the Eastern Qinling Mountains shows similar variations to the reconstructed temperature from nearby regions at both low-and high-temperature intervals, and they all indicate an increasing trend since the 1970s. Thus, our reconstruction of winter-half year temperature contains regional temperature signals to some extent. There is a great potential in reconstructing winter-half year temperature using Pinus armandii Franch trees growing at high elevations in the Eastern Qinling Mountains.
出处
《第四纪研究》
CAS
CSCD
北大核心
2009年第4期831-836,共6页
Quaternary Sciences
基金
国家自然科学基金项目(批准号:40601106
40811120030和30530050)
中国博士后科学基金项目(批准号:20060390914)资助
关键词
秦岭东缘
华山松
树轮宽度
冬半年温度
Eastern Qinling Mountains, Pinus armandii year mean temperature Franch, tree-ring width chronology, winter-half
