There are widespread calcium nodules in the lower-middle part of Jiufangtai section in Salawusu Riv-er Valley. The results show that carbon isotope and oxygen isotope of calcium nodules are characterized by scattered distribution and big differences in different lithology groups. And then,C4biomass can be estimated for each calci-um nodule by geochemical calculation. Combining with pollen records in the corresponding stratum, the evolution of vegetation cover in the cycle of glacial and interglacial period is discussed,which is similar with the results in the loess plateau. Meanwhile,the paleotemperature can be discussed quantitatively with the conventional formula of ox-ygen isotope. And the results confirm the last interglacial period is warmer. Therefore,it's an effective way to re-store temperature and vegetation. But it's also important to make comprehensive analysis and compare with another reference material.%通过对萨拉乌苏河流域酒坊台剖面中普遍发育的钙结核进行碳、氧同位素分析,结果显示各岩性组中同位素分布特征差异较大,无明显线性关系.利用钙结核中碳同位素值推算了不同岩性组中C3和C4植物的相对贡献量,结合孢粉数据,探讨了不同气候条件下植被演变情况,这与邻区的黄土高原研究成果基本吻合.同时,利用氧同位素和温度的经验公式,定量恢复了倒数第二次冰期-末次冰期的温度变化,其中末次间冰期表现为相对温暖的气候特征.总之,利用钙结核的碳氧同位素可作为定量恢复古温度、古植被的一种有效方式,但需要注意与其他指标进行综合对比分析.
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