Modelling of soil carbon sequestration by use of rice-straw mulching in two citrus orchards in Valencia (Spain)

The RothC carbon dynamics model was modified by including the straw mulch effects on SOC dynamics as observed on the field and, additionally, by modelling the soil water dynamics with the HYDRUS1D model. The SOC pools for the RothC simulations were assessed following the fractionation of Zimmerman et al. (2007). The model parameters were calibrated with the soil respiration data. The straw mulch model can be used for the estimation of the effects of the rice straw on the SOC in the short term. By changing the soil, climatic and agricultural practices inputs, the model can be applied to different fields in semiarid conditions, allowing the assessment of the soil carbon sequestration potential of different agricultural practices. However, the model still needs to be verified on long term field studies to deliver reliable long term sequestration projections.