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The functional relation between the δ18O values in the shell of gastropod Gyraulus si-birica and the air temperature in the warm half-yearly period, and that between Sr/Ca ratio and the precipitation in the warm half-yearly period were established by calibrating the δ18O and δ13C values, Sr/Ca ratio and Mg/Ca ratio in the shell Gyraulus sibirica, as well as the total organic carbon (TOC) and its δ13C values in the Xingcuo Lake sediment in the eastern Tibetan Plateau. The sequences of air temperature and precipitation in the last 200 years in the region were quantitatively recuperated on this basis. The results showed the following: (i) There was a negative corre-lativity between Sr/Ca ratio and the precipitation in the warm half-yearly period, its correlation coefficient was 0.86. (ii) There was an obviously positive correlativity between index δ18O and the running average temperature in the warm half-yearly period, its correlation coefficient was 0.89. (iii) Evolution of the air temperature and the
The functional relation between the δ18O values in the shell of gastropod Gyraulus si-birica and the air temperature in the warm half-yearly period, and that between Sr / Ca ratio and the precipitation in the warm half-yearly period were established by calibrating the δ18O and δ13C values, Sr / Ca ratio and Mg / Ca ratio in the shell Gyraulus sibirica, as well as the total organic carbon (TOC) and its δ13C values in the Xingcuo Lake sediment in the eastern Tibetan Plateau. The sequences of air temperature and precipitation in the last 200 years in the region were quantitatively recuperated on this basis. The results showed the following: (i) There was a negative corre-lativity between Sr / Ca ratio and the precipitation in the warm half-yearly period, its correlation coefficient was 0.86. (ii) There was an obvious positive correlativity between index δ18O and the running average temperature in the warm half-yearly period, its correlation coefficient was 0.89. (iii) Evolution of the air temperature and the