The post-fire succession in natural black pine (Pinus nigra Arnold) stands was analysed. Our research was done in the Trenta valley, where a fire took place in 2005, and above Log pod Mangartom, where a fire burned in 1979. The species composition of 22 sample plots of 10x10 m in areas of different burn severity and in unburned stands was recorded. The seedlings and saplings of tree and shrub species were also counted, and the amount of snags and logs wasrecorded. Hierarchical aglomerative clustering methods and principle coordinate analysis were used. The vegetation was also analysed according to plant strategies sensu Grime (CSR). Differences in regeneration between burn severity sites were determined using nonparametric tests, and correlation between coarse woody debris and regeneration was analysed. Significant differences were found between the recent burned area and control sites, but the older burned area is very similar to non-burned sites. The cover of dominant herb species (Erica carnea, Calamagrostis varia, Achnatherum calamagrostis) changed after the fire, and some new species, typical for burned areas, appeared. The succession is a transition from stress-tolerators to more competitive species, while the ruderal component is not significant. Pioneer species regenerated successfully in burned areas, while there was no difference in the regeneration of typical Fraxino orni-Pinetum nigraespecies. Coarse woody debris was found to have a positive impact on regeneration in the older burned area.
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