Abstract: [Objective]To reconstruct the history of climate change and reveal climatic characteristics from 1947 to 2014 in Miyun mountainous area, based on stable carbon isotope (δ¹³C) of tree-ring in Pinus tabulaeformis.[Method]In this paper, tree-ring samples of Pinus tabulaeformis in Miyun mountain area were collected to analyze tree-ring δ¹³C. Moreover, we eliminated the effect of atmospheric CO₂ from original δ¹³C series and establish the de-trend series (DS) of tree-rings. Then, regression equations were established based on analysis of the correlation of δ¹³C DS combined with temperature and precipitation, and further reconstructed the temperature and precipitation histories from 1947 to 2014.[Results] From 1947 to 2014:tree-ring δ¹³C series had a downward trend with a big fluctuation from 1997 to 2014. A quadric curve trend was found in tree-ring DS. Tree-ring δ¹³C DS is extremely and positively correlated with July temperature (r=0.719 7,P<0.01). The average temperature of July from 1947 to 2014 were reconstructed with regression method. Results showed that the average temperature of July firstly declined and then increased since 1980 with an average of 25.67℃. The tree-ring δ¹³C DS was extremely and negatively correlated with summer precipitation (r=-0.696 7,P<0.01). Summer precipitation data from 1947 to 2014 were reconstructed with regression method. Results showed that the average summer precipitation was 450.3 mm. After 1980, summer precipitation fluctuated sharply with an evident declining trend.[Conclusion]The response of tree-rings δ¹³C in Pinus tabulaeformis to July temperature was extremely and positively significant. The tree-ring δ¹³C values were extremely and negatively influenced by summer precipitation. Overall, the climate in Miyun mountainous area showed a fluctuated warming and drying trend from 1947 to 2014.

Key words: Miyun mountain area, tree-ring, δ¹³C, temperature, precipitation, climate change