RECONSTRUCTION OF JANUARY TO APRIL MEAN TEMPERATURE AT QINLING MTS FROM 1789 TO 1992 USING TREE RING CHRONOLOGIES

The mean temperature of January to April was reconstructed for the period of 1789 to 1992 using standard treering chronologies of Foping, Qinling, Shaanxi Province.The growth of Pinus tabulaeformis Carr., Abies chensiensis Van Tieghem and Tsuga chinensis Beisen at Muwangping, Guangtoushan, Sangebao and Sanguanmiao, whose altitudes are from 1500 to 2850 meters (a.s.l.), is significantly affected by the local January to April mean temperature.The correlation coefficient between the temperature series reconst ructed by the regression and the observation data is up to 0.60, with an equation confidence level of 0.01 and highly significant cross-verification testing parameters.A period of three to four years is found significant in the reconstructed series by the power spectrum method.The abrupt changes of standard deviation, in ten years scale, are detected around 1896 by means of the smoothing t Test, smoothing F Test and Lepage Test, apparing as the amplitude variation of temperature fluctuation.