Releases from Diffuse Sources to Water

This section presently covers only a limited set of nutrient loss maps from agriculture to water bodies.

The data on releases of agricultural nutrient stem from a range of different sources and data collection processes. This includes in particular data collected for the EEA’s State of the Environment report, reports from Member States in the context of the implementation of the Water Framework Directive, International River Basin Commission reports, National Environment Agency websites and research papers.

The data reported by countries reflect the use of a number of different calculation methodologies and are, typically, not directly comparable. Some approaches calculate or measure releases at the outlet of a catchment area (mouth) whilst others do so at the edge of the stream (edge). Large differences can arise between these two approaches due to in-stream nutrient processing. Best available and most recent data have been selected for preparing Europe wide maps but the data vary as to the reporting year. This is important since inter-annual variability in diffuse releases can be considerable, reflecting the variability in rainfall.