Properties of soil organic matter of Plaggic Anthrosols from Northwest Germany, Northwest and North Russia

Abstract

The study focuses on the properties of soil organic matter (SOM) of Plaggic Anthrosols from Northwest Germany, Northwest Russia and North Russia. As the sites differ in type of plaggen material and manner and duration of plaggen management, the aim was to find out whether these differences influence SOM. The studied soils show different SOM qualities by the C/N ratios of TOC, by the C/N ratios in the particle size fractions and IR spectra, the latter indicating the occurrence of keto- and carboxyl groups only for the German soil and amides exclusively for the Russian ones. The HCl-resistant organic carbon (OC) and the H₂O₂-resistant OC was largest and the HF-soluble OC was lowest in the Northwest Russian soil. With decreasing amounts in the sequence Northwest Germany, North Russia and Northwest Russia, the highest OC content was found in the fine silt and clay fractions. With the exception of the HF-soluble OC the parameters stay constant with depths of the plaggic epipedons, indicating no alteration with time. C/N ratios of TOC and different fractions as well as IR-spectra show distinct differences in the properties of SOM, reflecting different kinds of plaggen material and differences within the plaggen fertilization system.

Keywords:

• Plaggic Anthrosols
• refractory soil organic carbon
• organic carbon (OC) in density fractions
• OC in particle-size fractions
• IR-spectroscopy

Acknowledgements

This work was supported by the grant Gi-171/10-2 by the Deutsche Forschungsgemeinschaft. We thank Dr. Jutta Rach for scientific support in respect of IR spectroscopy, Ingeborg Eden, Brigitte Rieger, and Gunda Sängerlaub for their technical assistance. Special thanks to Dr. S. Babenko, E. Malyutin, Prof. O. Sokolov and M. Smirnowa for on-site help in Russia.