Identifying and Comparing Easily Accessible Frameworks for Assessing Soil Organic Matter Functioning

Soil organic matter (SOM) stocks are crucial for soil fertility and food provision and also contribute to climate change adaptation and mitigation. However, assessing SOM changes in cropping systems is difficult due to the varying quantity and quality of input data. SOM processes have been described by several models, but these are complex and require high amounts of input data. In this work, we identified and selected frameworks that simulate SOM pools and stocks as well as the effects of different management practices. We also required that the frameworks be easily accessible for farm-related end users and require limited and accessible amounts of input data. In all, six frameworks met our inclusion criteria: SOCRATES (Soil Organic Carbon Reserves and Transformations in EcoSystems), CCB (CANDY and-Carbon Balance), AMG, CENTURY, CQESTR, and RothC (Rothamsted Carbon Model). We collected information on these frameworks and compared them in terms of their accessibility, the model time steps used, the nutrient cycles included in the simulation, the number of SOM pools, and the agricultural management options included. Our results showed that CCB was the most robust of the frameworks considered, while AMG, CQESTR, and RothC performed the least well. However, all frameworks have strengths which may match the specific requirements and abilities of individual users.