Potenciál a limity přirozené obnovy smrku ve smíšených porostech na ŠLP Křtiny

The main aim of this work was to investigate the influence of relative diffuse radiation on the natural regeneration of a Norway spruce (Picea abies). There were chosen four research areason ŠLP Křtiny including the regeneration of the spruce in stand gaps with similar natural proportions (HS 441; SLT 3S, 4S, 4H; altitude 475-530 m n. m.). There were marked out four squared networks (5x5, resp. 10x10 m) where some features of spruce regeneration (density, height and the last height increase), herbs cover and relative diffuse radiation (ISF) were measured. The finding is that spruce seedlings sporadically appear at already 1-3% ISF. The highest density of spruce regeneration is around 18% ISF and the optimal increase (Ih > 10 cm) were over 27 % ISF. As far as density is concerned, south-eastern edge was found to be the most favourable. It is suggested to continue with border cutting with forward ameliorating and stabilizing tree species