(2014·长沙四县一市联考)湖水中盐分含量的变化可以反映湖泊水位

 (2014·长沙四县一市联考)湖水中盐分含量的变化可以反映湖泊水位以及气候的变化,下图示意青海湖近1.2万年以来盐分含量的变化情况。读图回答34题。

3.青海湖近1.2万年以来,最低水位出现的时间距今约(  )

  A3 900                                            B6 500

  C8 100                                           D1万年

4.与其他阶段相比,湖水盐分含量最小时期的气候特征可能是(  )

A.冷干                                                     B.温干 

C.热干                                                   D.温湿

答案

CD

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