Eutrophication can, therefore, be economically very costly and steps are being taken to reduce nutrient inputs to coastal waters. Intergovernmental organisations have agreed that we should halve nutrient inputs to waters around the North Sea and the Baltic Sea based on 1985 input values. If we achieve this, computer models suggest we should have healthy coastal waters by 2010.
What have we achieved in Europe so far?
Inputs to rivers
European directives on the treatment of sewage and use of phosphate free detergents have led to reductions in the inputs of phosphorous into our rivers and seas. However phosphorous concentrations are still high in coastal waters and it appears that phosphorous stored in sediments from earlier inputs is now slowly being released back into the water. Nitrate based fertiliser use has declined in Europe since the 1980's but nitrogen inputs to rivers from agricultural sources are still high.
Inputs to the atmosphere
Although there has been a general decline in emissions of air pollutants, levels of nitrogen oxides in the atmosphere are still high. Catalytic converters on new cars have reduced nitrogen oxide emissions but there has also been an increase in road travel which has partially offset the reductions in emissions per car. There has also been a decrease in ammonia emissions due to better management of animal wastes but we still have a long way to go to reach the targets which have already been set. One of the major problems with air pollution is that many species travel a long way from the place they are emitted to the place they are deposited. This may be in a different country, so we need European wide or even global action to reduce atmospheric inputs to coastal waters and this is politically difficult to achieve.
So we still have a way to go to reach the targets set by Intergovernmental Organisations such as The OSPAR Commission. By the time you read this, the situation may have changed. See if you can find the OSPAR web site and that of the European Environment Agency and find out how close we are to achieving our targets now.
About this page:
author: Dr. Lucinda Spokes - Environmental Sciences, University of East Anglia, Norwich - U.K. scientific reviewer: Prof. Tim Jickells - Environmental Sciences, University of East Anglia, Norwich - U.K. and Dr. Keith Weston - Environmental Sciences, University of East Anglia, Norwich - U.K. educationa reviewers: Francis Mudge - School of Education and Professional Development, University of East Anglia, Norwich - U.K. and Trevor Leggett - Chemistry Teacher, Norwich - U.K. last updated: 2003-10-16
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