An overview on long-term agro-ecosystem experiments: Present situation and future potential

Modern Long Term Agricultural experiments (LTAE) have a long history initiated when modern agricul-tural science was just at its beginning. After about 180 years from the start of the first of the classicalRothamsted experiments in 1843, these experiments still maintains a consistent appeal for researchersand the interest on LTAEs is growing, as shown by the increasing number of papers dealing with long-term effect of agricultural practices, frequently considering topics, such as sustainability, environmentalquality, species-adaptation impacts, that were never envisioned by the founders of classical LTAEs. How-ever, these experiments have numerous constraints and weakness that have to be clearly understoodand evaluated when using the data, especially for up-scaling or modelling purposes.Nevertheless, in our vision, the strengths and the opportunities of LTAEs are still overwhelming, par-ticularly if connected in networks allowing a standardisation of procedures and facilitating the access todata and to the experiments of researchers external to the institution hosting the LTAE.