Evaluation of Two Soil Carbon Models Performance Using Measured Data in Semi-arid Rangelands of Bajgah, Fars Province

Document Type : Research Paper


Department of Natural Resources and Environment Engineering, Shiraz University


The soil of rangelands is an important global carbon sink, in which any change makes a high impact on the CO2 emissions to the atmosphere and global warming. The capacity of this sink is controlled by complex interaction functions among various factors, including climate, soil properties, vegetation type, and management practices. For understanding the effect of these factors on soil carbon in long term, the soil carbon models have a vital role. The soil carbon models must be correctly validated for a specific region and ecosystem, then they can be used to simulate and predict changes in soil carbon. The main objective of this study was to evaluate the performance of RothC and Century models as the most widely used models in the soil carbon studies for semi-arid rangelands of Bajgah in Fars province. The R2 (determination Coefficient), r (correlation coefficient), RMSE (root mean square error), MAE (mean absolute error), MD (mean difference) and t-student test between simulated and measured values of soil organic C were used to evaluate the performance of RothC and Century models. Results showed although the Century model negligibly simulated SOC lower than the RothC model, but based on the statistical analyses, both models represented satisfactory results and their simulated values were consistence well with the measured values. Also the results of simulations by Century and RothC models showed that the SOC stocks will be increased during the years of 1987 to 2050 by 7.92% and 12.92%, respectively.


Main Subjects

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