Crop Rotation Index for measuring agricultural land use intensity

Crop rotations constitute a crucial way of managing farms. Scientific methods have studied rotations through different approaches. These either focus on the design of rotations, the performance of individual rotations (from a productivity, environmental performance, and/or soil recovery point of view), or the spatial pattern in the landscape. Despite these approaches, there is no method available to investigate the sustainability of a rotation at a large scale based on consistently followed agronomic principles in everyday farming practices. The novel Crop Rotation Index is proposed to fill this gap. To compute the Crop Rotation Index on a parcel basis, a sequence of crops over 6 years is evaluated by 8 indicators, where crops in the sequence are grouped together based on botanical families. These indicators represent, e.g., the frequency of crop categories in a rotation and the number of years between crops from the same category. The Crop Rotation Index was computed for the Netherlands using the parcel registry data. Results are presented at various spatial and temporal scales. Dutch arable regions in the south west and north east have an average value between 0.1 and 0.3, while grass-based systems in the center and north west have a value between 0.9 and 1.0. The results for the Province of Drenthe show that the western part is gradually becoming more intensive in arable crops, with values decreasing from 0.42 to 0.37 over a period of 5 years. A farm level case study on parcel sharing demonstrates that the Crop Rotation Index can capture complex land-sharing arrangements. The current version of the Crop Rotation Index can be extended with new indicators and crop categories and be applied in other regions. It is available as an indicator for performance monitoring in agriculture, supporting farmers in crop decisions, and as part rotation generation tools.