The nucleus and pilot farm research approach: experiences from The Netherlands

High application levels of fertilisers and agro-chemicals in The Netherlands have provoked increasingly stringent environmental policies. The development and evaluation of these policies have led to a shift in agricultural research. Starting in a tradition of factorial research, a systems-oriented approach was adopted. Building on results of earlier systems-oriented experimental research in the 1980s, an approach was developed where research on experimental farms increasingly became linked to a network of commercial farmers, serving as guinea pigs, applying newly developed fertiliser strategies, but also serving as discussion partners, providing new ideas and critically reviewing research results. This set-up, a systems-oriented experimental farm linked to a series of commercial farms, is referred to here as the NUcleus and Pilot Farm Research Approach. It has become the major research approach towards development of sustainable farming in The Netherlands, and is currently applied in projects oriented at dairy and arable farming. It was developed for arable farming during the 1980s and 1990s, whereas in the early 1990s an experimental farm was established for dairy farming. The present paper discusses the general research approach and background, characteristics and results of projects in dairy and arable farming, and compares them with other approaches. The research approach has important advantages, allowing evaluation of technical, economic and environmental performance under realistic conditions, embedded in a common bio-physical and economic environment, while the link with commercial pilot farms stimulates continuous mutual exchange of information. The major disadvantage, precluding statistical analyses due to lack of replicates and the continuous adjustments of the system, can at least partly be overcome through implementation of an intensive monitoring programme, and combining the research with modelling efforts and additional disciplinary research.