Identifying crop rotation practice by the typification of crop sequence patterns for arable farming systems - A case study from Central Europe

During the last decades crop rotation practice in conventional farming systems was subjected to fundamental changes. This process was forced by agronomical innovations, market preferences and specialist food processing chains and resulted in the dominance of a few cash crops and short-term management plans. Classical crop rotation patterns became uncommon while short rotations and flexible sequence cropping characterize the standard crop rotation practice. The great variety and flexibility in cropping management as a reaction to economic demands and climatic challenges complicate the systematization of crop rotation practice and make historical systematization approaches less suitable. We present a generic typology approach for the analysis of crop rotation practice in a defined region based on administrative time series data. The typology forgoes the detection of fixed defined crop rotations but has its focus on crop sequence properties and a consideration of the main characteristics of crop rotation practice: i) the transition frequency of different crops and ii) the appropriate combination of crops with different physical properties (e.g. root system, nutritional needs) and growing seasons. The presented approach combines these characteristics and offers a diversity-related typology approach for the differentiation and localization of crop sequence patterns. The typology was successfully applied and examined with a data set of annual arable crop information available in the form of seven-year sequences for Lower Saxony in the north-western part of Germany. About 60% of the investigated area was cropped with the ten largest crop sequence types, which represent the full range of crop pattern diversity from continuous cropping to extreme diversified crop sequences. Maize played an ambivalent role as driver for simplified rotation practice in permanent cropping on the one hand and as element of diversified sequences on the other hand. It could be verified that the less diverse crop sequence types were more strongly related to explicit environmental and socio-economic factors than the widespread diverse sequence types.