Nematode Assemblages Development Twenty-One Years after the Introduction of Meadow Soil into Bare Post Mining Spoil Heap

The revitalisation of soil fauna in post-mining soils is one of the ways in which we can slow down biodiversity loss. To investigate the effect of a meadow soil transplanted directly into the spoil substrate on the colonisation of a spoil heap, we used nematodes as a tool for an assessment of success in soil fauna recolonisation. Three blocks of meadow topsoil (10 Chi 3 Chi 0.4 m) were dug out and transported as intact as possible into a bare substrate of spoil heaps near Sokolov (Czech Republic). The soil samples were taken at the beginning of the experiment (1997) and then, after 19 years (2016), were transported into blocks (B) in their surroundings in a 2 m distance (I) and, finally, 30 m from the transported blocks as a control (C), to compare and assess the complexity of soil food web. Nematode total abundances were highest in B plots and lowest in the nearby I plots at the beginning, whereas later, their abundances were highest in I plots and lowest in the control (C) plots. However, due to the high variability, abundances were statistically insignificant. The trophic composition of I plots became similar to the composition in B plots in the late phase; however, the high occurrence of predators in C plots showed a running succession even after 19 years. Our results together with previous works from the same experiment support the findings that the level of soil development has a larger impact on recolonisation by soil fauna than the migration barrier itself.