| According to tree-ring width samples in eight sites of the south slope on the north TianShan Mountain in Yili, including Huocheng, Yini and Nileke, tree-ring width Chronologies were developed. The results indicated that the Fenshuiling chronology contained more climatic information than the others by comparing and analyzing some parameters of tree-ing chronologies in Yili area. Single correlation calculation between the chronologies of tree-ring width in eight sites and maximum temperature(from July to August last year) and precipitation(from July last year to June current year) of the weather station indicated that the correlations were significant. And it has distinct physiological significance with the greast single correlation coefficient is 0.664(a=0.00000025) and -0.624(a=0.00000184). Taking into account the impact of precipitation and temperature on tree-ring at that time, the following year and another year, using the regional tree-ring chronology, more than 250 years maximum temperature and precipitation series were well reconstructed. It was verified that the reconstructed precipitation and temperature series were reliable. Analyzing more than 250 years maximum temperature and precipitation series show that:1) The growth of Schrenk Spruce of the south slope on the north TianShan Mountain in Yili is intensively limited by the temperature(from July to August last year) and precipitation(from July last year to June current year). The result has distinct physiological significance. It was verified that the reconstructed precipitation series was reliable.2) There were ten dry periods bellow its mean and nine wet periods above its mean in the 255 years.The maximum precipitation stages occurred from 1869 to 1877, which was 7.9% more than the long-term mean; the minimum precipitation stages occurred from 1757 to 1766,which was 12.7% less than the long-term mean; the longest wetter stages occurred from 1949 to 1971, continuing 23 years, which was 6.0% more than the long-term mean;and the longest drier stages occurred from 1972 to 2000 continuing 24 years, which was 1.7% less than the long-term mean.There were eight periods bellow its mean and eight periods above its mean in the 255 years.The maximum warmer stages occurred from 1853 to 1869, which was 0.6℃more than the long-term mean; the minimum colder stages occurred from 1870 to 1876, which was 0.8℃less than the long-term mean; the longest warmer stages occurred from 1912 to 1947, continuing 36 years, which was 0.2℃more than the long-term mean;and the longest colder stages occurred from 1888 to 1911, continuing 24 years, which was 0.1℃less than the long-term mean.3)In the 256 years , the number of wet partial years is more than the dry partial. The minimum precipitation year occurred in 1753, which was 50.0% less than the long-term mean; The maximum precipitation year occurred in 1941, which was 40.0% more than the long-term mean.According to the mean of the maximum temperature in the 255 years, we can find: the maximum temperature was 31.6℃occurred in 1916, which was 1.8℃more than the long-term mean ;the minimum temperature was 27.8℃occurred in 1875, which was 2.0℃less than the long-term mean.4) There were 4 abrupt changes of the precipitation(from July last year to June current year) in 1807,1831,1911,1971. Abrupt changes from high to low in 1807 and 1911, and abrupt changes from low to high in 1831 and 1971.There were six abrupt changes of the temperature(from July to August last year) in 1778,1803,1831,1854,1871 and 1909. Abrupt changes from high to low in 1778,1831 and 1871, and abrupt changes from low to high in 1803,1854and 1909. There were significant change periods of 2.6a,3.3a,3.4a,8.1a,and 17a at 0.05 level in the long-term precipitation series reconstructed; and there was 2.7a of the mean maximum temperature.
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