Linking farm management to agri-environmental indicators: recent experiences from The Netherlands

Agriculture in industrialised countries is under increasing pressure. Trade liberalisation, increasingly stringent environmental policy and climate change provide both a threat and a challenge to farmers and agricultural research. The Netherlands has a tradition of intensive agricultural research and extension projects. Recent systems oriented, interactive and dynamic research projects were extremely data intensive, involving time-consuming monitoring programmes. As such monitoring programmes are costly, alternatives are pursued. Agri-Environmental Indicators (AEIs) were used in communication between researchers, farmers, extension officers and policy makers. General requirements for AEIs are that they should (i) refer to relevant policy issues, (ii) be based on sound science (recognising that their development is an evolving process), (iii) be quantifiable, (iv) be relevant for target groups involved, (v) be easy to interprete, (vi) be cost effective, and (vii) be able to facilitate communication In this paper we evaluate experiences of AEI use in Dutch research projects, presenting applications predominantly in nitrogen management, but also in carbon and water management. The paper lists applications in both dairy and arable farming. AEIs, especially farm nitrogen budgets, appeared excellent instruments for communication. AEIs should however be applied with care, as they simplify spatially and temporally highly variable processes. The use of nitrogen budgets to compare operational management of different groups of farmers only is valid if these groups are homogeneous with respect to their activities and internal flows. As a rule, the scale at which AEIs can be safely applied should reflect the temporal and spatial variability of the relevant soil processes. Application at too large a scale will easily lead to neglect of the possible large variations and ' hence ' emissions taking place. AEIs should further be applied in integrated farm management evaluation. Application to a limited aspect of farming, e.g. nitrogen or water management, easily leads to the neglect of less favourable effects in other aspects. As processes determining the nutrient, water, and carbon cycles are highly interacting, management of either should also consider management of the other compounds.