Vertisols and Cambisols had contrasting short term greenhouse gas responses to crop residue management

In sustainable agriculture crop residues management should consider the interactions between soil and residue properties which can affect the decomposition and global greenhouse gases (GHGs) emission. Through a laboratory experiment, we investigated the effect of the management (incorporation and surface placement) of wheat and faba bean residues on their decomposition and CO2, CH4 and N2O emissions from two soils, a Chromic Vertisol and an Eutric Cambisol. In the Vertisol, wheat residues increased the CO2 emission more than faba bean when left on the surface while no differences among residues were observed when incorporated. In the Cambisol, faba bean emitted more than wheat when left in the surface and less when incorporated. Total CH4 emissions were higher in faba bean in Cambisol for both management and only when applied in surface in Vertisol. Total N2O emission in the Vertisol was higher when faba bean was incorporated and wheat was left on the surface. In the Cambisol, wheat addition increased total N2O emissions by 20% compared to faba bean, with no differences between managements. Our study confirmed that contrasting properties among tested soils resulted in significant interactions with residues own degradability and their placement affecting residue decomposition, soil C and N dynamics, and GHGs emission.