Applying indicators, threshold values and proxies in environmental legislation: A case study for Dutch dairy farming

Environmental research has contributed significantly since 1990 to a strong reduction of environmental pollution associated with dairy farming in the Netherlands. To judge possible pollution, state indicators and threshold values are distinguished. Threshold values for: (i) N and P in ground- and surface-water, (ii) air quality in terms of ammonia and greenhouse gasses and (iii) deposition rates of N on nature areas, are still exceeded. New approaches are needed as the EU dairy quota system will expire in 2015 and production is likely to increase. Four are suggested: (i) change the top-down character of regulations to a bottom-up self-governing procedure where farmers receive clear guidelines and are challenged by government and assisted by research to meet them. The future commitment of farmers is crucial as "the low environmental fruit" has been harvested; (ii) abolish confusing and overly complex proxy systems and focus on direct measurement of state indicators, using newly developed sensing systems and proper statistical sampling procedures for expressing variability; (iii) make the derivation of threshold values for environmental state indicators more science-based and transparent and start with focusing on individual farms and nature areas to be followed by upscaling to regions and the entire country. (iv) Follow the recommendations of the Trojan report and develop comprehensive regional management plans and a strategic plan for the entire country. Environmental research has been fragmented and often reactive rather than pro-active. Recent research on farm level, using life cycle analysis, applies an integrated approach to study water, air and soil qualities as well as economic aspects and can therefore form the basis for future management plans on farm level and for regional and national plans, all to be focused on sustainable development. (C) 2010 Elsevier Ltd. All rights reserved.