précipitations hors forêt

CONT: En absence de toute pollution, l'eau de pluie a un pH proche de 5,5. Pour la placette, le pH des précipitations hors couvert forestier est de 5, celui des précipitations sous couvert forestier est légèrement plus 4,8.

CONT: Hydrochemical investigations were initiated within the framework of a national research programme on forest decline. The objective was to measure simultaneously on plot and catchment scales, the effects of acid atmospheric inputs at all the levels of the ecosystem. Atmospheric pollutants, open field precipitation, throughfall and soil solutions at various depths and in different stands, spring waters and stream waters have been monitored continuously for almost 10 years.