Modelling Crop Rotations and Nutrient-Balances in Organic Farming Systems

Abstract

To provide a tool for the generation and evaluation of crop rotations in organic farming systems, the Leibniz-Centre for Agricultural Landscape Research ZALF e.V. has developed the software tool ROTOR in Microsoft (MS) Access beginning in 1997. Its database contains information on crops and crop production activities (CPAs). These CPAs obtained through expert knowledge are sets of crops and their cultivation methods, the resulting nitrogen (N) delivery as well as the N-need, describing the time range from stubble tillage until the harvest. They facilitate the generation of crop rotations crucial to organic farming based on a static rule-based model. It allows furthermore to evaluate nutrient-balances and yield projections, taking site-specific factors into account. The fact that ROTOR runs within the commercial software MS Access and the software’s structure and database that have grown over the years, becoming less maintainable, made a software re-engineering indispensable. The newly developed version of ROTOR is a standalone software written in Python with a PostgreSQL database. Although the core principles of the underlying models have remained, the calculations of nutrient-balances were refined, whereas the generation of crop rotations was comprehensively revised. Its modular structure allows for better maintainability and scalability.