Can a farming systems approach help minimize nitrogen losses to the environment?

Farming practices are often developed to tackle one aspect of a problem without due regard to other possible consequences. Nutrient management systems commonly concentrate on maximizing yields rather than attempting to balance the needs of the crop with the desire to minimize contamination of the environment. Particular problems are shown to be associated with utilization of animal manures on arable crops, and the move towards soil conservation practices, especially the use of cover crops. We suggest that nutrient budgets provide a suitable format for developing a systems approach. We consider the issues associated with managing nitrogen for whole farm systems, taking account of the need for efficient production and protection of the environment from losses by leaching and in gaseous form. Finally, we suggest a role for expert groups in developing a systems approach.