The long-chain alkenones in the upper layers of bottom sediments of salt lakes in Southern Siberia as a potential biomarker of paleo-climate

Abstract

The long-chain alkenones in the upper layers of the bottom sediments of ten salt lakes in Southern Siberia were collected as a bio-marker for paleo-limnological studies in the summer 2019. The quantitative and qualitative composition of long-chain alkenones were determined by means of gas chromatography mass spectrometry. Also, the possibility of using this class of compounds as a salt-sensitive bio-marker for paleoclimatic reconstructions in the corresponding regions was assess. The results showed that the extracted alkenones are a mixture of several fractions with different lengths of the carbon chain and the number of double bonds. The alkenone C37:4 fractions positively correlate with the salinity of the studied lakes and can serve as a marker of salinity in paleo-climatic reconstructions.