利用贺兰山东西坡78个油松树芯样本建立了标准年表,分析发现1~8月平均气温是树木宽度生长的重要限制因子之一,且有明确的树木生理学意义.在此基础上模拟重建了贺兰山地区1776~1999年1~8月平均气温,重建序列的解释方差为43.3%(F=21.422,p<0.001).重建中相对高温的年份有:1805~1818,1828~1857,1899~1907,1919~1931,1968~1995;相对低温的时段为:1858~1872,1883~1895,1935~1953.重建气温10年滑动曲线表现出3个明显的气温缓慢上升阶段(1766~1853,1862~1931,1944~1995),每个升温期之后随之而来的是10年左右的快速降温,即贺兰山1~8月气温有缓慢升温而后又快速降温的特点.功率谱分析表明1-8月气温存在70、10.77、2.62、2.19、2.11年的准周期.
Tree-ring standardized chronologies are developed with 78 cores obtained from eastern and western Mt. Helan. Both STD and RES chronologies correlate negatively with the different periods of early half year temperature, especially January to July (August) (JJ/JA) temperature. It has evident physiological meaning that wide rings were formed when JJ(JA) temperature was low and narrow rings were formed when JJ(JA) temperature was high. Based on this analysis, we reconstructed mean temperature from January to August in the period 1776-1999, and the explained variance is 43.3% (F = 21.422, p〈0.001). The comparatively high temperature periods in reconstruction are 1805-1818, 1828-1857, 1899-1907, 1919-1931, and 1968-1995; and the comparatively low temperature periods are 1858-1872, 1883-1895, and 1935-1953. Ten year moving average curve presents three slow uplifting periods of 1766-1853, 1862-1931, and 1944-1995. Each temperature increase was followed by a sudden temperature decrease of about ten years, that is to say, the JA temperature has the character of slow increase and sudden decrease. The 70- and 10.77-year periodicities detected in the tree-ring growth series correspond respectively to the Gleissberg (80a) and Schwabe (1 la) periodicity of solar activity, and the 2.11-2.62 year cycles are considered to be influenced by QBO (Quasi-Biennial-Oscillation) and the local environmental change.