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树木年轮定年准确、连续性强、分辨率高,并且易于获取复本,已经成为过去气候变化重建的主要手段之一。通过分析青藏高原南部南木林地区大果圆柏的树木年轮宽度变化及其对气候因子的响应,发现树木生长季前期的温度与树木径向生长变化呈正相关关系,而夏季温度与树木径向生长呈负相关关系;年总降水量(上年7月到当年6月)是当地树木径向生长的主要限制因子,相关系数为0.66(P<0.01),表明南木林地区树轮宽度变化可以指示该地区年总降水量变化。南木林树轮年表(1560—2008年)的突变检验结果显示,该年表在年代际尺度上存在1627年和1829年左右的突变点,表明南木林地区降水量在过去499a间经历了两次突变。对树木年轮标准化年表的功率谱分析表明,南木林树轮记录具有150a、100a、75a、60a、50a以及3.7a和3.06a的显著周期,其中3.7a和3.06a周期可能与ENSO有关。
The annual growth rate of tree rings is accurate, continuous, high resolution, and easy to obtain replicas. It has become one of the major means of rebuilding climate change in the past. By analyzing the change of tree ring width and its response to climatic factors in the southern woodland of southern Qinghai-Xizang Plateau, it was found that there was a positive correlation between the temperature and the radial growth of trees in the early growth season, while the correlation between summer temperature and tree radial The annual total precipitation (from July last year to June of the same year) was the main limiting factor of the radial growth of local trees with a correlation coefficient of 0.66 (P <0.01) Indicate the annual total precipitation changes in the area. The results of the mutation test of the South Woods Tree Wheel Chronology (1560-2008) show that this chronology has abrupt change points on the interdecadal scale between 1627 and 1829, indicating that the precipitation in the southern forest region has experienced two Sub-mutation. The power spectrum analysis of the annual tree ring standardized chronological table shows that the tree records of the southern forest have significant periods of 150a, 100a, 75a, 60a, 50a and 3.7a and 3.06a, of which 3.7a and 3.06a periods may be related to ENSO.