The effects of nitrogen deposition & climate change on freshwaters in the UK

July 2004 — June 2007

As well as sulphur, deposition of nitrogen-containing pollutants (nitrogen oxides and ammonia) can contribute to acidification through leaching of nitrate from soils. Despite reductions in nitrogen oxides emissions of 40% and in ammonia emissions of 15% in the UK since 1990, monitoring data show that levels of nitrate in UK freshwaters are not in decline. Similarily, concentrations of nitrate in rain so far show no statistically significant downward trend. The reasons for these observations need further investigation.

In the current research programme the Freshwater Umbrella will examine the relative importance of current and historical nitrogen deposition in nitrate leaching, together with the factors controlling the rate of leaching. An assessment will also be made of the influence of climate change on the response to and potential recovery from acid and nitrogen deposition.

Work programme

The scientific work programme is split into four work packages. For further details click on the work package titles in the list below: