ZLV Online

Abstrakt

Silver fir (Abies alba Mill.) represents a key forest tree species whose ecological and silvicultural importance is increasing under conditions of global climate change (GCC) in Europe. This study assessed stand structure, biodiversity, productivity, and radial growth in relation to climatic variables (air temperature and precipitation) in 109–126-year-old mixed stands of silver fir and Norway spruce (Picea abies [L.] Karst.) in the West Bohemian Uplands, Czech Republic (408–602 m a.s.l.). Stand volume in these mature mixed silver fir stands ranged from 237 m3/ha on nutrient-poor pine sites to 459 m3/ha on more fertile sites. Overall biodiversity, expressed as the comprehensive diversity index (B), ranged from 3.87 to 5.76 and increased with a higher proportion of mixed-species admixtures. Climatic fluctuations significantly influenced the radial growth of both species. Silver fir exhibited greater tolerance to variability in air temperature. Still, it was susceptible to late-spring frosts, whereas Norway spruce was negatively affected by the synergistic effects of high air temperatures and summer drought. July emerged as the most influential month for radial growth in terms of air temperature, while February was critical for precipitation. Silver fir demonstrated a stronger growth response to monthly air temperature and precipitation variations compared to Norway spruce, particularly on nutrient-poor sites. These findings confirm silver fir as a keystone species due to its shade tolerance, high ecological plasticity, and resilience to variable climatic conditions, highlighting its potential role in adaptive management of mixed forests under GCC scenarios.