Remote mountain lakes as indicators of diffuse acidic and organic pollution in the Iberian peninsula (AL:PE 2 studies)

The extent of diffuse atmospheric chemical pollution above the Iberian peninsula was examined using several mountain lakes as sentinel ecosystems. Particular attention was given to acidic and organic pollution of water and sediment, compositions of populations of benthic diatoms, zooplankton, aquatic macroinvertebrates and fish, and the accumulation of organic pollutants in fish. Lakes of the Iberian peninsula did not show severe anthropogenic acidification. Levels of acidic pollutants were low, though pH values were in the range characteristic of sensitive lakes. The status of the organisms surveyed supported this conclusion. Lakes in the Pyrenees showed the highest organic pollutants fluxes and declines in alkalinity and pH.