Abstract: The relationship between tree growth and meteorological factors of Picea schrenkiana in upper and lower forest of eastern and western Tianshan Mountains was studied by climatological method, to reveal the radial growth of P. schrenkiana in response to climatic factors in different regions and the sensitivity of P. schrenkiana under the influence of climate warming. Through a large number of data collection and analysis, the results showed several interesting points. First, the statistical characteristics of chronology were more significant and radial growth of trees was more sensitive to climatic factors in Zhaosu than in Hami. Second, the growth of trees in the two regions was affected by temperature and precipitation. From western to eastern Tianshan Mountains, the significantly positive correlation was reversed to be significantly negative between tree radial growth and temperature in the lower forest boundary, while the relationship between tree growth and precipitation in the upper forest boundary changed from significantly negative to significantly positive. Third, at the lower elevations of Zhaosu and Hami, climate had a stronger influence on the growth of P. schrenkiana during 1984-2015 with increasing temperature than during 1957-1983 with decreasing temperature, whereas the growth of trees displayed reversed patterns in response to climate between the two periods at higher elevations of Hami. Furthermore, as the temperature increased, the promoting effect of temperature on the radial growth of trees increased significantly in the lower forest boundary of Hami in April, while the inhibitory effect of temperature on the radial growth of trees increased significantly in the lower forest boundary of Zhaosu and Hami in June. However, the promoting effect of temperature in June on P. schrenkiana growth decreased significantly in the upper forest boundary in Hami. The promoting effects of precipitation increased significantly for the radial growth of P. schrenkiana in lower forest boundary in Zhaosu and in upper forest boundary in Hami in May and June, respectively. The inhibitory effect of temperature in April and precipitation in October on P. schrenkiana growth decreased significantly in the lower forest boundary in Hami. As the temperature increased, the relationship between tree growth and the local climate factors changed insignificantly, because the precipitation in the upper forest boundary in Zhaosu can meet the growth of trees.

Key words: chilling, extreme value analysis, log-normal distribution, Gumbel distribution, Weibull distribution, Pearson-III distribution