C-in and C-outputs, rates and mechanisms of C-sequestration and C-stabilization of post-agrogenic soils exemplified by Luvisol chronosequences of Russia

• Applicants: Professorin Dr. Luise Giani; Professor Dr. Yakov Kuzyakov
• Subject Area: Soil Sciences
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 280532651

Until recently arable land use decreased considerably in many countries of the world. Russia is at the top of the list of countries with abandonments of arable lands. There most abandonment applies to Luvisols of the deciduous forest zone. It is known that post-agrogenic soils show a high carbon(C) sequestration potential and that their properties as well as preconditions for soil organic carbon (SOC) stabilization and SOC sequestration change during development towards the natural occurrence. But mechanisms of SOC stabilization, rates of changes in C pools, and the relation to C input and C output are not well-understood. Hence, this research program aims at analyzing the changing processes of SOC pools, mechanisms of SOC stabilization, and microbial communities and their activities of post-agrogenic Luvisols of the deciduous forest zone of Russia. Given that the processes begin and stop at different points in time, that they do not run linearly a chronosequential approach with distinct periods of abandonment is a promising tool. The investigations cover SOC stocks, SOC sequestration, SOC accumulation rates, SOC enrichment of passive C pool, entering rates of new C into active and passive C pools, SOC mineralization in macro and microaggregate, and microbial communities and their activities. The further focus of the study is the integration of these soil-intern processes into a broader ecosystem context by quantification of C inputs and C outputs. For evaluation the development of the SOC stocks exceeding the time spans of the chronosequences modeling will also be performed. Because Luvisols are the most widespread soils of temperate climate regions of Eurasian and America and represent the major group for potential arable lands, the findings of this study can be transferred to many areas worldwide.

• DFG Programme: Research Grants
• Co-Investigator: Professorin Dr. Michaela Dippold