To main content
Norsk
Publications

Review and revision of empirical critical loads of nitrogen for Europe

Report
Year of publication
2022
External websites
Cristin
Contributors
Roland Bobbink, Christin Loran, Hilde Tomassen, Khalid Aazem, Julian Aherne, Rocío Alonso, Frank Ashwood, Sabine Augustin, Jesper Bak, Vegar Bakkestuen, Sabine Braun, Andrea J. Britton, Emiel Brouwer, Simon J. M. Caporn, Tomáš Chuman, Heleen de Wit, Thomas Dirnböck, Chris Field, Héctor García Gómez, Markus Geupel, Liv Guri Velle, Erika Hiltbrunner, Alice Casas James, Laurence Jones, Per Erik Karlsson, Lukas Kohli, Sirkku Manninen, Linda May, Reto Meier, Michael P. Perring, Anne-Katrin Prescher, Eva Remke, Tobias Roth, Thomas Scheuschner, Axel Ssymank, Carly Stevens, Jan-Erik Thrane, Hans Tømmervik, Simon Tresch, Liisa Ukonmaanaho, Leonard H Van Den Berg, Elena Vanguelova, Kayla Wilkins, Susan Zappala

Summary

This report describes the scientific background and results from the review and revision of empirical critical loads of nitrogen that had been established for Europe in 2011 under the auspices of the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP Convention). In 2020, the Coordination Centre for Effects started a project under the LRTAP Convention to bring empirical critical loads up to date. New relevant information from studies (2010 - summer 2021) on the impacts of nitrogen on natural and semi-natural ecosystems was incorporated in the existing European database on empirical critical loads of N (CLempN). The current review and revision used for the first time gradient studies to evaluate and determine the ClempN. The CLempN were structured according to the updated classification used within the European Nature Information System (EUNIS). Consensus on the results was reached in a UNECE expert workshop on empirical critical loads of nitrogen (26-28 October 2021, Berne, Switzerland), organised by the Swiss Federal Office for the Environment (BAFU), the Coordination Centre for Effects, and the B-WARE Research Centre. The results, as presented in Table 1 of the Executive Summary, show that in many cases the outer ranges of the empirical critical loads have decreased. The resulting 2021 European database includes both revised and newly established value ranges of CLempN for each EUNIS class. The outcomes of this report are of major importance for the protection of N-sensitive natural and semi-natural ecosystems across Europe. This knowledge is used to support European policies to reduce air pollution.