Establishing a Diagnosis: Inventorying, Monitoring and Assessing
Résumé
Improving air quality is a major challenge for public health and the environment. Assessing the contribution of agricultural activity to air pollution and the resulting impacts is a prerequisite for recommending mitigation practices. More important, their long-term adoption can only be justified by performing a real-time assessment of their effectiveness. Since the 1990s, using emission indicators, air contamination levels and environmental impacts has indeed become a widespread means of supporting decision-making at different levels, risk management and public policy assessment. However, this assessment is made difficult owing to the complex network of processes involved and the variability in pollutant emission and deposition. This chapter first details the methodologies implemented for emission inventories, used to better target the largest contributing sources, to check whether national commitments have been met, and to assess the trends. It also presents observation networks established to monitor background air pollution, deposition as precipitation, gases and particles in rural and forest areas, and impacts on terrestrial ecosystems. Finally, it outlines the indicators used to assess the impacts of agricultural practices on human and ecosystem health via the atmospheric compartment and it gives examples of their practical use to manage pollution risks, evaluate agricultural practices or compare agricultural products.