地理学报 ›› 2003, Vol. 58 ›› Issue (1): 90-100.doi: 10.11821/xb200301011

• 论文 • 上一篇    下一篇

柴达木东缘山地千年祁连圆柏年轮定年分析

邵雪梅1,2, 方修琦1,3, 刘洪滨4, 黄磊1   

  1. 1. 中国科学院地理科学与资源研究所,北京 100101;
    2. 中国科学院地球环境研究所,西安 710075;
    3. 北京师范大学资源与环境科学系,北京 100875;
    4. 国家气候中心,北京 100081
  • 收稿日期:2002-08-14 修回日期:2002-11-11 出版日期:2003-01-25 发布日期:2010-09-09
  • 作者简介:邵雪梅 (1957- ), 女, 浙江人, 研究员, 博士生导师, 从事气候变化及树轮气候学研究。E-mail: shaoxm@igsnrr.ac.cn
  • 基金资助:

    中国科学院知识创新项目(KZCX2-314和KZCX1-10-02); 国家重大基础研究发展规划项目 (G1998040811)

Dating the 1000-year-old Qilian Juniper in Mountains along the Eastern Margin of the Qaidam Basin

SHAO Xuemei1,2, 1,3, FANG Xiuqi4, 1   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    2. Institute of Earth Environment, CAS, Xi'an 710075, China;
    3. Beijing Normal University, Beijing 100875, China;
    4. National Climate Center, Beijing 100081, China
  • Received:2002-08-14 Revised:2002-11-11 Online:2003-01-25 Published:2010-09-09
  • Supported by:

    Knowledge Innovation Project of CAS, No. KZCX2-314, KZCX1-10-02; National Key Basic Research Special Fund, No. G1998040811

摘要:

针对中国干旱区生长的树木缺失轮和伪轮多等具体情况,及常规树轮定年方法应用于中国干旱地区时所遇到的问题,本文以柴达木盆地东缘山地上生长的千年祁连圆柏树轮定年工作为例,详细探讨了在中国干旱地区建立树轮定年年表的方法体系及技术路线,对常规的工作方法提出新的改进。这包括:采样中要采集不同树龄、不同小生境且大复本量的样本;交叉定年工作要按一定的工作程序;安放缺失轮时要同时考虑窄轮和宽轮变化的一致性;用多种方法对定年和轮宽量测值进行检验等。这些方法的具体应用有助于在中国干旱地区建立定年准确、千年尺度的树轮年表。

关键词: 柴达木东缘山地, 树木年代学, 轮宽变化型, 树轮年表, 交叉定年, 千年祁连圆柏

Abstract:

In this paper, the methods for developing the master chronologies for 1000-year-old Qilian Juniper (Sabina przewalskii Kom.) are introduced in detail. Since the studied sites are located in the arid region of northeast Qinghai-Xizang Plateau, the tree-ring cores sampled contain a certain number of missing rings and several false rings. To assure the proper placement in time of each growth layer for the 1000-year-old trees, some improvements were made in the practice of master chronologic development. Firstly, trees with a variety of ages were sampled besides very old trees. The large sample depth benefited the identification of missing rings for cores from old trees and avoided the possibility that all collected specimens could be missing a ring for any one year. Secondly, cores from younger trees and from trees that exhibit a little width variation were selected to do the skeleton plot first and cores with many missing rings were done last when the ring-width pattern was known. Thirdly, inferring where rings may be missing was made based on the agreement among the narrow rings as well as among the wide rings. If the agreement of wide rings is not so good and there were some missing rings, the chronology from nearby sites was used to infer the year of missing ring occurrence. Finally, several methods, such as the computer program COFECHA and the line plots were used to examine the dating and the measurements of ring width for a site. The number of cores without missing rings and time span covered by them were also inspected to avoid the possibility that all collected specimens were added a missing ring for any one year. The Gleichlaufigkeit statistics was used to examine the dating agreement between master chronologies of different sites.

Key words: the Qaidam Basin, dendrochronology, ring-width pattern, tree-ring chronology