Modeling the Organic Carbon Dynamics in 112 Years Old Permanent Manurial Experiment Plot Using the Rothamsted Carbon Model.

An assessment was conducted on the performance of Rothamsted Carbon Model (RothC) model’s in simulating Soil Organic Carbon (SOC) dynamics over a 112-year period involving organic and mineral fertilization practices in a sandy-loam Alfisol. The crop rotation of the experiment included maize and sunflower. The model performance was evaluated by Coefficients of Root Mean Square Error (RMSE) and Efficiency factor (EF). Subsequently, model was utilized to forecast SOC dynamics over a 25-year period under similar pedoclimatic conditions. The results of the RothC simulations demonstrated Nitrogen, Phosphorus and Pottassium (NPK) + Farm Yard Manure (FYM) increased SOC stocks at the 0–15 cm soil depth (RMSE = 1.36, EF = 0.66). The SOC stocks reached steady state for the treatments FYM (every year) (RMSE = 0.99; EF = 0.49). RothC clearly simulated SOC reductions in control plot (RMSE = 12.37; EF = 0.58) and inorganic fertilizers applied plot (RMSE = 1.17; EF = 0.64). The carbon sequestration potential of the treatment which received NPK+ FYM is 147 kg ha−1 yr−1 during 2032 and it showed an improvement over the future years. Similarly, FYM treatment plot showed a sequestration potential of 96 kg ha−1 yr−1 and it showed a static rate in the future trend. However, 100% NPK plot shows declining trend which was 59 kg ha−1 yr−1. In conclusion, our findings indicate that the RothC model effectively predicts C dynamics in the Permanent Manurial Experiment plot, provided accurate initialization and appropriate parameterization of the model are ensured. [ABSTRACT FROM AUTHOR]