Effects of lime and artificial acid rain on the enchytraeid (Oligochaeta) fauna in coniferous forest

Effects of lime and artificial rain of varying acidity on the enchytraeid fauna were studied in 4 field experiments in coniferous forest. Artificial rain was applied 5 months per year in quantities of 25 or 50 mm per month and with pH values from about 6 to 2. The “rain” was produced by mixing groundwater and sulphuric acid. The greatest total abundance of enchytraeids and the greatest population densities of Cognettia sphagnetorum and Mesenchytraeus pelicensis were found in plots supplied “rain” of pH 6, pH 4 and pH 3. Their abundances were lowered by additional acidification (pH 2.5 and 2) and also by liming. Species like Enchytronia parva and especially Enchytraeus buchholzi and Fredericia parnoniana were mostly stimulated by liming.