The Study Of Dendroclimatology In The West Of Altay, Xinjiang Province

In this paper, we compared some statistics results of the five tree-ring standardized chronologies of the West of Altay from ARSTAN program, the results indicated that the Shaleha chronology contents most climatic information and the Kemu chronology contents lest climatic information. Contrasting the correlation coefficients between the tree-ring chronologies showed that the correlation coefficient of the Shaleha chronology and the Hanasinan chronology is 0.676 and is highest, which located near the upper limit of the forest. But the correlation coefficient of the Hanasibei chronology and the Kemu chronology that located near the edge of the forest is 0.586, and the tow chronologies have low correlation with the three chronologies that located near the upper limit of the forest. Established three kinds of chronologies, according to samples of West of Altay, the Single correlation screen indicated that the correlation were significant between five tree-ring residual chronologies and the precipitation from June to September, and the correlation were significant between five tree-ring autoregressive standard chronologies and the monthly average temperature from May to September. The maximum correlation coefficient were -0.556 and 0.426. At the same time, this result was distinct physiological significance. Using five tree-ring residual chronologies in Shaleha (t, t+1), the precipitation in the recent 524 a was well reconstructed, and using five tree-ring autoregressive standard chronologies in Shaleha (t+1) and Jikeyin (t, t+2), the monthly average temperature in the recent 365 a was well reconstructed. And the equation reconstructed was stable by crossing-test. The precipitation sequences analyzed find out that in the recent 524 a, the precipitation reconstructed has nine wet periods above its mean and nine dry periods bellow its mean. The precipitation series in the recent 524 a from June to September reconstructed in the West of Altay, have significant changing periods of 34.8 a, 5.0～5.1 a, 4.3～4.4 a, 3.9～4.0 a, 3.7 a and 3.4 a. The temperature sequences analyzed find out that in the recent 365 a, the temperature reconstructed has five warm periods above its mean and five cold periods bellow its mean. The monthly average temperature series in the recent 365 a from May to September reconstructed in the West of Altay, have significant changing periods of 13～14 a and 7 a. The abrupt changes of precipitation occurred in 1518, 1548, 1634, 1765 and 1856, and the abrupt changes of temperature occurred in 1684, 1706, 1746, 1767, 1802, 1839, 1859, 1881, 1909 and 1949.We compared some statistics results of the eight tree-ring standard width and gray chronologies of Kemu sampling sites in the West of Altay from ARSTAN program, the results indicated that the statistics results of the tree-ring standard width chronologies are all higher than the tree-ring standard gray chronologies'. The correlation between the eight tree-ring standard width and gray chronologies index and the precipitation and monthly average temperature of Buerjin weather station showed that there is the positive correlation between the latewood gray chronology and precipitation from June to August, and the positive correlation between the earlywood gray chronology and monthly average temperature from December to February before the prior growing season. The maximum correlation coefficients are 0.462 (α=0.001) and 0.362 (α=0.02). At the same time, an explanation of its physiology was presented. The fluctuations cycles of the three tree-ring standard width chronologies appeared the periods of 14 a and 3.4 a. The five tree-ring standard gray chronologies all showed the periods of 2.2～2.4 a.