The role of nutrient availability in microbial soil organic matter formation and stabilization in agricultural soils of different C saturation status

(Co)investigator from the Department: Eva Kaštovská
Funding provider: The Czech Science Foundation
Duration: 2019 to 2021

Project goals: 
We aim to understand how nutrient availability and substrate complexity affect the rate and efficiency of microbial SOM formation in soils differing in C saturation status. We further aim to identify conditions supporting accumulation of stable SOM in such soils.

Project description:
The soil organic matter (SOM) is of fundamental importance in maintaining soil productivity due to the retention of carbon, nutrients and water. Inadequately managed arable soils lose their SOM in the long-term thus current farming practices should initiate and support SOM accumulation. Stable SOM is importantly contributed by compounds of microbial origin. Factors influencing the efficiency of microbial metabolism such as type (complexity) of plant inputs and soil nutrient status thus directly affect microbial SOM formation, composition and stability. The proposal aims to study microbial processes responsible for substrate transformation into microbial SOM in conditions of different soil nutrient status and to identify conditions supporting stable SOM accumulation in arable soils. In laboratory and mesocosm experiments combining above-mentioned factors, we will focus on microbial growth rate and efficiency and SOM accumulation in soils differing in C saturation status. We will further asses total soil C balance and the composition and stability of the formed SOM.