Fifty years ago, the Swedish long-term soil fertility experiments were started by the late Prof. Sven L. Jansson to “elucidate the nature of soil fertility, to provide a basis for soil evaluation and soil conservation”. At that time, the use of mineral fertilisers was still minor and a major concern was the consequences for soil fertility of completely replacing animal manure with mineral fertilisers due to separation of animal and crop production. The main questions were the extent to which different cultivation measures affect yields and the levels of production that could be reached and maintained under different conditions.
The experiments have provided valuable insights into soil fertility in relation to crop production and fertilisation. They still answer questions that arise regarding new practices and their impact on soil and the environment. They are used as a platform for new research tasks and modelling driven by structural changes in agriculture. Furthermore, differences developing in soil conditions over time provide valuable information for addressing complex interactions in an appropriate way. This report recognises the great significance of long-term field experiments for our understanding of agricultural production, soil fertility and environmental issues and illustrates main findings from on-going long-term activities.