Lipids of Cold Soils of Transbaikalia

Abstract

The ¹³C-NMR spectra and elemental composition of lipids of gray forest soils (Greyic Phaeozems), dispersed carbonate chernozems (Haplic Chernozem Hypocalcic), and chestnut soils (Kastanazems) of Western Transbaikalia were analyzed. The contribution of carbon in lipids to the total organic carbon was calculated. This is the first characterization of the lipid fraction of organic matter in cold soils of Western Transbaikalia. An analysis of the spectra, including the assignment of signals from ethoxy groups, phenol derivatives, and alkene fragments, as well as an indication of the ranges of chemical shifts characteristic of certain types of carbon nuclei, were carried out. The content of various types of structural elements in the studied lipids was compared. Based on the obtained results, the main part of lipids consisted of esters and fatty acids. Analysis of the composition of lipids showed that the content of carbon and hydrogen atoms was 65‒73 and 8‒10%, respectively. The high concentration of oxygen atoms in lipids indicated that functional groups containing oxygen were concentrated in the aliphatic part of the lipids. The share of lipid carbon in the total reserve of organic carbon was 6.5% for chestnut soils, 5.8% for gray forest soils, and 4.1% for dispersed carbonate chernozems.