Al:Pe projects: Water chemistry and critical loads

Abstract

Water chemistry data on which all the investigations in the AL:PE 1 (Acidification of Mountain Lakes: Palaeolimnology and Ecology) and AL:PE 2 (Remote Mountain Lakes as Indicators of Air Pollution and Climate Change) projects are based, are available for 28 lakes in U.K. (Scotland), Italy, Norway and France (AL:PE 1) and in Svalbard (Norway), Ireland, Austria, Spain, Portugal, Poland, Slovakia, Slovenia and Russia (AL:PE 2). The results show high sulphate concentrations in some mountain lakes in all the countries. Nitrate and sulphate concentrations have different distribution patterns among the sites. A gradient in acidification from north (Norway) to central Europe (via U.K. to Italy) is identified for the AL:PE lakes by means of multivariate data analysis. Critical loads and their exceedance are calculated, where sufficient information is available, both according to the leaching of S, and of S plus N from the catchment. The pattern of critical load exceedance demonstrates an increasing importance of nitrate from Norway via U.K. to Italy. Leaching of N was of considerable importance to the acidification of lakes in the Italian Alps. The projects receive financial support from the European Union.