© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1434-2944/11/205-0164 * Corresponding author Internat. Rev. Hydrobiol. 96 2011 2 164–174 DOI: 10.1002/iroh.201011251 MILOSLAV DEVETTER* , 1 and JAN FROUZ 1, 2 1 Institute of Soil Biology, Biology Centre AS CR, Na sádkách 7, 370 05 České BudČjovice, Czech Republic; e-mail: devetter@upb.cas.cz 2 Institute of Environmental Studies, Faculty of Science, Charles University, Benátská 2, 12000 Praha 2, Czech Republic Research Paper Primary Succession of Soil Rotifers in Clays of Brown Coal Post-Mining Dumps key words: soil rotifers, post mining dumps, primary succession Abstract Changes in rotifer soil communities along a primary succession chronosequence was studied on brown coal post mining areas near Sokolov, NW part of the Czech Republic. The chronosequence of unreclaimed plots was 2, 11, 14, 20, 43 years old. The rotifers were extracted from soil samples using a modification of the Baermann funnel method with combined light and temperature gradients. In total, 34 taxa of soil rotifers were identified throughout the study. The most common species were Encentrum arvicola, Adineta vaga, A. steineri, Habrotrocha rosa, H. elegans, H. filum, Macrotrachela quadricornifera and M. nana. Rotifer abundance varied from 4 ± 2 ∙ 10 3 to 516 ± 488 ∙ 10 3 individuals m –2 . Species number per sample increased with age of the plot (r = 0.45, P = 0.003). The most impor- tant environmental variables which significantly affected rotifer community were wood cover, sodium concentration and age of the plot. Pioneer plant species occupied 2 and 11 year old plots, 14–20 year old plots were covered by Salix caprea shrubs and a forest formed by Betula pendula and Populus tremuloides developed on the 43 year old plot. Some species were ubiquitous and present throughout the chronosequence (Macrotrachela quadricornifera). Among the pioneer species were Encentrum incisum, Habrotrocha rosa and Macrotrachela papillosa, 14–20 years old plots were preferred by Adineta vaga, E. arvicola, H. filum and M. nana, while the oldest plot was dominated by Adineta steineri and Encen- trum mucronatum. 1. Introduction Open coast mining represents a type of human activity, which strongly disturbs large areas of the landscape. Material covering coal layers is excavated and deposited on spoil dumps. Such heaps are formed of pure mineral material which had no contact with the surface for ages (in our case for about 20 million years). Natural processes which occur in this new environment allow primary succession of microbial (FROUZ and NOVÁKOVÁ, 2005; BALD- RIAN et al., 2008) and plant communities (PRACH, 1987; FROUZ et al., 2008) as well as soil formation (ŠOURKOVÁ et al., 2005) with many soil animal groups (FROUZ et al., 2001; PIŽL, 2001; HÁNċL, 2001, 2003).