Petr Plohák Hana Svehlakova ^* Barbara Stalmachová Miroslava Goňo Tomáš Dvorský

• VSB-Technical University of Ostrava, Ostrava, Czechia

The soil seed bank is an important source of data on the state and dynamics of vegetation. It is especially important in landscapes exposed to disturbances, which have lost their functions. For our research, a post-mining area in the region of the Upper Silesian Black Coal Basin was selected, whose relief and ecosystems are strongly disturbed by underground mining and are currently also affected by ongoing climate change. The soil seed bank is one of the pillars of landscape succession, and its importance is also growing in restoration practice. Data collection for our research took place in the territory of two waterlogged subsidence basins in the Karvina region, Czech Republic. A study compared two methods: seed extraction and cultivation. At specific locations, we collected 540 soil cores, which were pooled into 108 composite samples. The extraction method yielded four times as many seeds as the cultivation method. However, the recorded number of species was not significantly higher in the case of the extraction method (66 species) than in the case of the cultivation method (60 species). The extraction method identified a significantly higher number of seeds of phanerophytes. For other life forms, the methods demonstrated a more balanced performance. A statistically significant effect of the presence of the tree layer on the number of species obtained by the extraction method was demonstrated (p = 0.0016). There is also a statistically significant difference between the selected analysis methods in terms of the length of the captured seeds (p = 0.0012) and their seed mass (p = 0.00047). The level of qualitative (Sørensen index) and quantitative similarity (NMDS analysis) of the species composition of seeds in both methods is low. Using both methods simultaneously, we can capture a larger number of species, which also increases the similarity between the soil seed bank and the above-ground vegetation. The suitability of using both methods at the same time was also proven using rarefaction. With twice the number of samples, 86% (extraction); 84% (cultivation) and 87% (combination of both methods) of seeds of plant species would be captured in the soil seed bank.