阿勒泰西部树轮年表特征分析

Analysis of the Tree-ring Chronological Characteristics in the West of Altay

通过对比阿勒泰西部5个标准化树轮宽度年表的多项年表特征参数,发现沙勒哈年表包含的气候信息较多,而柯姆年表所含的气候信息可能最少。通过年表间互相关系数的对比,发现2个位于森林上限的沙勒哈年表与哈纳斯南年表的相关最高(0.676)。而接近下树线森林边缘的哈纳斯北年表和柯姆年表的相关达0.586,却与3个位于森林上限的年表相关较低。通过相关普查得出,阿勒泰西部3个位于森林上限的年表与该区域当年6—7月的月平均气温呈正相关,其相关系数最高为0.426,显著性水平达0.0035,与当年6—8月的降水量呈负相关,其相关系数最高为-0.535,显著性水平达0.0002,而两个接近下树线森林边缘的年表与该区域当年1月的降水量呈正相关,其相关系数最高为0.45,显著水平达0.0019,且二者的相关具有明确的树木生理学意义。在0.10的显著性水平上,除吉克音年表外,其他4个年表均具有2.4a的变化准周期。此外,吉克音年表和柯姆年表均存在13.5a和14.4a的变化准周期,哈纳斯南年表和沙勒哈年表均存在23.0a和38.3a的变化准周期。通过对比年表高低频信息含量,发现阿勒泰西部年表中高频信息含量一般高于低频信息含量。

In this paper,some statistics results of the five tree-ring standardized chronologies of the west of Altay from ARSTAN program were compared.The results indicated that the Shaleha chronology contains the most climatic information and the Kemu chronology contains the least.The contrast of the correlation coefficients between the tree-ring chronologies showed that the correlation coefficient between the Shaleha chronology and the Hanasinan chronology is 0.676 and is the highest,which located near the upper limit of the forest.But the correlation coefficient between the Hanasibei chronology and the Kemu chronology that located near the edge of the forest is 0.586,and the two chronologies have low correlation with the three chronologies that located near the upper limit of the forest.The correlation analysis showed that there is negative correlation between the tree-ring width index of the three chronologies which located near the upper limit of the forest and the precipitation from June to August（the highest coefficient-0.535,the significance level 0.0002）,and positive correlation with the mean temperature from June to July in the prior growing season（the highest coefficient 0.426,the significance level 0.035）;there is positive correlation between the tree-ring width index of the two chronologies which located near the lower limit of the forest and the precipitation of January（the highest coefficient 0.455,the significance level 0.0019）,and the correlation has certain physiological significance.At 0.10 significance level,the tree-ring width index fluctuations of the other four chronologies appeared the period of 2.4-year except the Jikeyin chronology.Besides,the Jikeyin chronology and the Kemu chronology all showed the quasi-periods of 13.5-year and 14.4-year,and the Hanasinan chronology and the Shaleha chronology all showed the quasi-periods of 23.0-year and 38.3-year.The content of the high-frequency information is stronger than that of the low-frequency information in the tree-ring chronologies of the west of Altay.