Accuracy, robustness and behavior of the STICS soil–crop model for plant, water and nitrogen outputs: Evaluation over a wide range of agro-environmental conditions in France

• STICS v8.2.2 soil–crop model was evaluated over a large and varied dataset using its standard set of parameters.
• Level of accuracy is 10–50% for plant, soil water and nitrate outputs.
• Model reproduces well trends arising from contrasted agro-environmental conditions.
• Errors are weakly dependent on the agro-environmental conditions tested.
• Model accuracy and robustness is considered good for scenario testing and large scale use within the conditions tested here.

Soil–crop models are increasingly used as predictive tools to assess yield and environmental impacts of agriculture in a growing diversity of contexts. They are however seldom evaluated at a given time over a wide domain of use. We tested here the performances of the STICS model (v8.2.2) with its standard set of parameters over a dataset covering 15 crops and a wide range of agropedoclimatic conditions in France. Model results showed a good overall accuracy, with little bias. Relative RMSE was larger for soil nitrate (49%) than for plant biomass (35%) and nitrogen (33%) and smallest for soil water (10%). Trends induced by contrasted environmental conditions and management practices were well reproduced. Finally, limited dependency of model errors on crops or environments indicated a satisfactory robustness. Such performances make STICS a valuable tool for studying the effects of changes in agro-ecosystems over the domain explored.