Main Article Content
The aim of the present study was to investigate the composition of spontaneousplant cover and the physicochemical properties of the substratum of spoil heaps of theSiersza hard coal mine in Trzebinia (southern Poland) abandoned in 2001. Floristic andsoil analyses were performed in 2011. The substratum was very diverse in terms of texture(sand: 55–92 %, clay: 6–38 %), nutrient content (total C: 1.3–41.0 %, total N: 0.05–0.49 %,total Ca: 0.5–7.3 %) and pH (3.7–8.7). Moreover, total thallium concentration in the substratumwas high, ranging from 6.0 to 14.6 mg kg–1. Plant cover varied from 50 to 95 %.The number of plant species per 4m2 varied from 6 to 29 and correlated negatively with totalcarbon content (r = –0.85, p < 0.01), and positively with sand content in the substratum(r = 66, p < 0.05). The highest number of species per area unit was observed on a humussubstratum, where initial soil has developed on the part of carboniferous waste rock spoilunder 20–30 year old trees, and the lowest on carbon shale with coal and culm. Among 197plant species, most belong to Asteraceae, Fabaceae, Poaceae and Rosaceae families.Hemicryptophytes (49%) and terophytes (18%) predominated. The investigated area wasprimarily colonized by native species spread by the wind. However, invasive alien speciesalso had a significant share (8%) in the plant cover.