An investigation into the long-term effect of soil transplant in bare spoil heaps on survival and migration of soil meso and macrofauna

To study the effect(s) of soil transplantation on survival and colonization of post-mining spoil heaps by soil fauna, we transplanted blocks of topsoil (3 × 10 × 0.4 m) from a well-developed meadow into the bare post-mining heap in Sokolov coal mining region (Czechia) in 1995. The soil meso and macrofauna were studied in two periods, namely 1995-1997 (initial period) and 20 years later in 2015-16 (follow-up period). We sampled transplanted blocks (Transported), overburden at a 2-m distance from the blocks (Adjacent), and overburden at a 30-m distance from the blocks (Control). The number of mites was highest in the Transported, in the initial period, and at the Control 20 years after- i.e. in the follow-up period. Judging by their higher densities, for Lumbricidae, and most of the miscellaneous macrofauna, Transported was favored in both time periods. The high macroarthropod densities in the Transported position, even after 20 years, and the low microarthropod densities in the Adjacent position together suggest a limited role of transplanted soil blocks in the colonization of the spoil overburden, signifying that soil development of the spoil overburden might be even more critical than the migration barrier.