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通过对青藏高原东部若尔盖盆地兴措湖 5 0年来Gyraulussibirica壳体元素及同位素分析 ,并与器测气象资料的比较 ,建立了兴措湖记录与对应的降水和气温间的函数关系 ,探讨了湖泊记录所指示的气候环境意义 .结果表明 :青藏高原东部兴措湖地区腹足类生物在夏半年形成壳体 ,它所记录的是夏半年而不是全年的气候环境信息 ;Gyraulussibiria壳体Mg/Ca比及δ18O指标与夏半年气温有一定的相关性 ,其中壳体δ18O指标对气温变化更敏感 ,δ18O与夏半年气温滑动平均间的变率为 1.64‰ /℃ ,均值比为 0 .2 8‰ /℃ ;Sr/Ca比、δ13 C指标与夏半年的降水量关系较密切 ,尤其是Sr/Ca比随降水量波动呈显著相关变化 ,Sr/Ca变化与降水间的平均变率 (d (Sr/Ca) /dP)为 - 0 .0 4 5 /mm .
Through the analysis of the element and isotopic composition of the Gyraulussibirica shell in the Zozo Lake in the Zoigê Basin, east of the Qinghai-Tibet Plateau, and comparison with the measured meteorological data, the relationship between the Xinghuo Lake record and the corresponding precipitation and temperature is established. The results indicated that the gastropods of the Xingtu Lake area in the eastern Qinghai-Tibet Plateau formed shells in the summer half year, which recorded climate and environmental information in the summer half year instead of the whole year. The climate information of the Gyraulussibiria shell Mg / Ca ratio and δ18O index have some correlation with summer temperature. Shell δ18O index is more sensitive to temperature change, δ18O and summer sliding temperature average temperature is 1.64 ‰ / ℃, mean ratio is 0.828 ‰ / ℃; Sr / Ca ratio, δ13C and precipitation in summer are closely related, especially the Sr / Ca ratio has a significant correlation with the fluctuation of precipitation, the change of Sr / Ca and the average rate of change between precipitation (Sr / Ca) / dP) is -0.045 / mm.