The molecular structure and elemental composition of humic substances from Albeluvisols

Abstract

The structure of humic and fulvic acids from a Siltic Albeluvisol and a Stagni-Histic Albeluvisol (Siltic) was studied. It was found that the development of hydromorphism results in the enrichment of humic substances with aliphatic fragments. The presence of unoxidised aliphatic fragments in the structure of humic substances, in combination with anaerobic conditions, favours the gley process in the Stagni-Histic Albeluvisol (Siltic). Features of the structural composition of humic substances are related to the humification rate: this process is slowed in northern regions and accelerated in southern regions, where humic substances are more humified.

Keywords:

• humic and fulvic acids
• solid-state ¹³C NMR
• soil moisture
• Albeluvisols

Acknowledgements

This work was supported the Russian Foundation for Basic Research, projects 07-04-00285 and 09-04-90820.