Ecole-chercheurs internationale Methodological Approaches to System Experiments
Agriculture has to evolve to contribute to sustainable development worldwide. In order to do so, new cropping systems and livestock farming systems must be designed to produce agricultural goods that are satisfactory in quantity and quality, while ensuring a good income to farmers and preserving the environment, notably natural resources. There is growing evidence that the implementation of agroecology concepts is a major springboard to attain satisfactory compromises between these different objectives.
The agroecological transition is knowledge intensive. Experimental approaches are a cornerstone to produce knowledge and technical references. The progresses made in agriculture during the last century strongly relied on experimental approaches. However, these experiments were mainly factorial: the effects of one factor, or of a few factors, on a limited range of agricultural performances were analysed using standardised experimental designs. The consideration of the complexity of management and of a larger range of performances requires a systemic approach, where entire cropping or livestock systems, defined as combinations (over defined periods of time and space) of technical operations are tested. For more than two decades, in several European countries, researchers and advisers have been facing methodological problems related to so-called “system experiments”. It was time to formalise and share methodological guidance to system experiments.