Development of soil fauna at mine sites during 46 years after afforestation

At the afforested overburden heap,,Langteichhalde" (lignite mining district Berzdorf, Eastern Germany) a long-term study of the soil fauna (since 1961) was completed by new investigations between 1996-1999 taking microfauna, mesofauna and macrofauna into consideration. Detailed information about the present development of testate amoebae, nematodes, lumbricids, spiders and harvestmen, oribatids, centipedes, millipedes, apterygotes, ants, carabid and staphylinid beetles are briefly compared with the earlier succession of these groups. Generally, both the species inventory as well as diversity points to a change from open landscape communities to woodland associations, albeit in a more or less poor condition. Differences of the settlement depending on deciduous or coniferous afforestation type and surface profile (crests, troughs) are discussed. The contribution of soil organisms to organic matter decomposition was studied by bait lamina tests, the minicontainer technique, and by calculating the potential zootic decomposition level. At the deciduous afforestation the overall soil biological activity reaches the level of natural woodland soils very quickly (after 10 - 20 years), even though based upon the continuing development of soil faunal entities. Primarily coniferous afforestations show an impeded decomposing activity, even if developing in a mixed wood. During succession of the mine site community an interesting interrelationship between parts of the soil fauna, especially between lumbricids and microarthropods, can be demonstrated.