摘要
The Qinghai Lake is the largest saline lake in China. The authors study the compositions of n-alkanes and their hydrogen isotope in sediments from the lake, and discuss the genesis of their compositions by the comparison with previous study results of plants from the lake and its surrounding areas. The results show that the n-alkanes in the surface and core sediments have a similar distribution which reflects the source from terrestrial herbaceous plants in the surrounding regions of the lake. The hydrogen isotopic compositions of n-alkanes in the surface and core sediments are also similar, which indicates that n-alkanes in the sediments were derived from terrestrial herbaceous plants in surrounding regions of the lake. This study demonstrates that the hydrogen isotopic compositions of n-alkanes in lake sediment reflect the biological source hydrogen isotopic signals that are related to paleoclimate. Therefore, δD values of n-alkanes in lake sediment can be used to indicate paleoclimate.