Earthworms (Lumbricidae) from a surface layer and wireworms (Elateridae) of forest stands in the anthropogenically-disturbed area of the Děčínská vrchovina Upland (Czech Republic)

Abstract

In the area negatively affected by air pollution in the past, the earthworm assemblages and the occurrence of wireworms (Elateridae) in forest ecosystems were evaluated in relation to site conditions. From soil samples taken in 38 stands (Fagus, Betula, Alnus, Quercus, Pinus, Larix, Abies) earthworms and wireworms were extracted by means of Tullgren funnels. Eudominant species (Dendrobaena vejdovskyi, D. octaedra, D. illyrica) are typical representatives of forest ecosystems of the Ore Mountains. Relationships were proved to a tree species creating a forest stand and the pH of Ah horizon. The area is characterized by the generally low diversity of earthworms particularly in young stands of beech and Norway spruce. Faunistically rich sites occurred only in a mixed stand (birch, mountain ash, larch) and in a blue spruce monoculture. Reduced abundance of earthworms in the organic matter of mounds was surprising. The type/form of soil preparation, forest weed cover and the age of trees did not affect significantly the earthworm assemblages. The abundance of wireworms was increased in pine and larch stands and reduced in alder and blue spruce stands. The increasing pH value negatively affected the abundance of wireworms.