中国东部亚热带地区树轮δ13C方位变化的谐波分析

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 中国东部亚热带地区树轮δ13C方位变化的谐波分析 DOI: 10.5846/stxb201109191378 作者: 作者单位: 临沂大学资源与环境研究院,临沂大学化学与化工学院,南京师范大学地理科学学院,南京师范大学地理科学学院,中国科学院南京地理与湖泊研究所湖泊沉积与环境开放实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(41072139); 山东省自然科学基金项目(Y2008E15); 临沂大学博士启动基金项目(BS07014) Analyzing the azimuth distribution of tree ring δ13C in subtropical regions of eastern China using the harmonic analysis Author: Affiliation: Research Institute of Resources and Environment, Linyi University,School of Chemistry,College of Geographical Science, Nanjing Normal University,College of Geographical Science, Nanjing Normal University,Lake Sediment and Environmental Opening Laboratory of Nanjing Geography and Limnology Institute, Chinese Academy of Sciences Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:对浙江天目山2株柳杉(Cryptomeria fortunei Hooibrenk ex Otto et Dietr,分别简称为CF-1,CF-3)及南京紫金山8株马尾松(Pinus massoniana Lamb.,分别简称为PM-1-PM-4,PM-7-PM-10)树轮δ13C平均值方位序列及2株柳杉树轮δ13C方位平均值年序列进行了谐波分析。分析结果及相关性检验表明,树轮δ13C值的方位变化有很强的谐波特征。第1次谐波与第2次谐波分量的方差贡献率占原序列总方差的百分比,除PM-8与PM-10低于70%外,其余均在70％以上,其中,CF-1与PM-9分别达到了93%和96.5％。第1次与第2次(或第3次)谐波的拟合序列与原序列的相关性极高,相关系数均在0.8以上,都通过了0.05的显著性检验,而且,两次谐波的拟合度均比较高,均在75％以上,拟合效果较好。分析结果表明,用2π与π(PM-1与PM-7为2π/3)两个主要谐波周期就可以较好地拟合各树轮δ13C序列的方位变化。初相位值的计算结果显示,第1、2次谐波的初相位值存在明显差异,这表明:不同树体2次谐波振幅的峰值出现的方位区域不同,即以2π及以π(PM-1与PM-7为2π/3)为周期的树轮δ13C方位变化的极大值并不出现在固定方位区。所以,两次谐波叠加的结果使树轮δ13C极值出现的方位区域更复杂。对天目山2株柳杉树轮δ13C各方位均值年序列的分析结果表明,2树轮δ13C极值均存在明显的年际漂移,其极大值出现频率较高的方位随树木生长坡向而发生转移。两树轮相比,多数年份其δ13C的主极大值出现的方位区基本发生45°的方位转移。而主、次极大值叠加的结果却使δ13C极值出现的方位基本发生90°的转移,这种极值转移的方向及转移度数与2株树所在坡向的变化和坡向变化度数正好相一致。 Abstract:The azimuth average sequence of δ13C in tree rings of two Cryptomeria fortunei Hooibrenk ex Otto et Dietr disks(named CF-1, CF-3,respectively) and eight Pinus massoniana Lamb disks(named PM-1-PM-4, PM-7-PM-10,respectively), as well as the average orientation annual series of δ13C in tree rings of Cryptomeria fortunei, were investigated using harmonic analysis. Data related to Cryptomeria fortunei and Pinus massoniana were collected from Tianmu Mountain, Zhejiang Province and Purple Mountain of Nanjing, Jiangsu Province, respectively. The analysis showed the azimuth variations of δ13C in tree-rings had very strong harmonic characteristics. The variance contribution of the first and second harmonic components as a percentage of the total variance of the original sequence were mostly above 70%, including CF-1 and PM-9 which reached 93% and 96.5%, respectively, the two exceptions were PM-8 and PM-10. The correlation coefficients were greater than 0.8 (P ＜ 0.05) between the first and the second (or the third) harmonic fitting sequence, and the original sequence. The two harmonic fitting sequences were relatively high, both above 75%, and exhibited a good fit to the data. The azimuth variations of δ13C in tree rings could be well explained by two harmonic cycles of 2 π and π (PM-1 and PM-7 were 2 π/3). The initial phase values of the first and the second harmonics had clear differences. This indicates that the doubling of the harmonic amplitude peak in different trees was present in different azimuth regions:the maximum of the azimuth variations of δ13C in tree rings with 2π and π harmonic cycles were in different regions. When the results of the two harmonic cycles were superimposed, the orientation of the maximum δ13C in tree rings became complex. Harmonic analysis of the average annual sequences of δ13C in different azimuths of C. fortunei showed that the extremes have obvious inter-annual drift. The azimuths of the δ13C maximum changed with slope of tree growth. In most years, the azimuth of the δ13C maximum transferred 45°, but when the main and secondary maximums were superimposed, it became 90°. The change in the direction and magnitude of the δ13C maximums are consistent with the slope changes in the growth of the two trees. 参考文献 相似文献 引证文献