Data and code for "Functionally rich crop rotations increase calorie and macronutrient outputs across Europe"

16 long-term experiments are included in the study, representative of arable crops in Europe and covering a wide range of pedoclimatic conditions.

We identified the candidate long-term experiments via referral from colleagues and the scientific literature, and contacted the person(s) appearing as currently responsible for the experiment. The long-term experiments included satisfy five criteria (at least 10 years of data and two rotations, cereal in all rotations, all crops grown every year and diversity not confounded with other treatments; for details, see Methods in Vico et al. Nature Food). We checked whether a long term experiment met such criteria with the person(s) currently responsible for of each long-term experiment. For each long-term experiment, we used all the available data from rotations meeting the criteria. We included all the available data available in terms of years, rotations including cereals, and replicates. However, if the rotations were altered during the experiment, we retained only the data relative to the longest period with unchanged rotations. For one site (Säby_LTE), we did not consider the rotations with residue burning. Within each experiment, the rotations were set up according to a randomized design. The number of replicates depended on the long term experiments, with 8 of them not replicated. Crop yields for each rotation, year, replicate/other treatment were aggregated to whole rotation outputs of calories, carbohydrates, proteins and fats, assuming common retail products for each crops, and considering three scenarios of use of forage crops.

The analyses rely on crop yield collated in randomly selected areas within each plot and then data aggregated by site, crop rotation, replicate/other treatment and year, transforming marketable yields in calorie and macronutrient outputs, assuming common retail products for each crop. The crop yield data had been collected at each long-term experiment, by local personell and following the local protocol.

Crop yield data and basic management information were provided by the contact person(s) currently responsible for the long-term experiment. The data were homogenized in format and combined in a single dataset of yields per site, crop, year, treatment(s). Yield data were later transformed in calorie and macronutrient outputs at aggregated per site, year, and treatment(s).

Data were originally collected in 16 long-term experiments across Europe