Modelling soil carbon and nitrogen cycles during land use change. A review

Previous reviews on carbon sequestration under perennial energy crops include some unrelated to soil organic carbon, some without experimental evidence, and some focused on specific geographical regions.

“Although there have been previous reviews on C sequestration under PECs [8–11], some of these were either unrelated to SOC [12, 13], or did not report any experimental evidence [1, 14, 15], or focused on specific geographical regions [16].”

Non-linear interactions between decomposition rate and temperature can exist for different pools, with the effect greatest at lower temperatures and for slowly decomposable compounds but least for old SOC.

“Finally, non-linear interactions between decomposition rate and temperature can exist for different pools, with the effect being greatest at lower temperatures and for ‘slowly decomposable’ compounds but least for ‘old’ SOC [14].”

Depth-dependent decomposition has been implemented by water and heat flux models, empirical coefficients, or including C transport such as diffusion and adsorption of DOC.

“In summary, depth-dependent decomposition has been implemented by introducing (i) water and heat flux models [14, 169] or (ii) empirical coefficients [40] or (iii) including C transport, i.e. diffusion and adsorption of DOC [42].”

Soil water dynamics are considered a key parameter in all SOC models applied to PECs.

“Soil water dynamics are considered a key parameter in all SOC models applied to PECs [14, 15].”

The effect of soil moisture on SOC decomposition is complex and non-linear; a single moisture threshold for decreased microbial activity and soil respiration does not exist.

“The effect of soil moisture is complex and non-linear; a single moisture threshold for decreased microbial activity and soil respiration does not exist [14].”