In the present study a dynamic stand growth model for Norway spruce (Picea abies (L.) Karst.) forests was developed from data of 99 research plots, which had been measured between one and seventeen times in northwestern and southern Germany. In this model, the initial stand conditions at any point in time are defined by three state variables (dominant height, basal area and number of trees per hectare), and they are used to estimate stand volume for a given projection age. The model uses three transition functions to project the stand state variables at any particular time and a state function to estimate the stand volume. Two of these transition functions were derived by expanding a base model and considering two sitespecific parameters and the third one was derived considering one site-specific parameter. All the functions were fitted simultaneously using full information maximum likelihood and the base-age-invariant dummy variables method. The values of the critical error statist...

Many climatic models predict significant temperature rises in mountainous regions, which may influence the distribution of montane species. Thermophilization observed or predicted in mountainous areas to date may accelerate the shift of forest-forming trees to higher areas. Our aim was to detect how the health status of Norway spruce (Picea abies [L.] Karst) and dwarf mountain pine (Pinus mugo (Turra)) changes along an altitudinal transect, and to what extent the health status of trees depends on the studied environmental variables. Field measurements were performed in the Alps with an acoustic tomograph, which is able to determine the extent and exact location of rotten parts without damage. In the case of P. abies, the stands are currently considered to be the healthiest between 1000 and 1500 m, while they show the greatest deterioration near the lower limit of their distribution. At the lower limit of the vertical distribution of the species, a retreat of 50–100 m is expected. We...

Introduced tree species have become increasingly important in the context of the ongoing climate change. This paper focuses on the dendrochronology of the most widespread introduced tree species in the British Isles – Sitka spruce (Picea sitchensis [Bong.] Carr.) – in comparable soil conditions in England, Czechia, and Slovakia. The research aims to evaluate the growth dynamics and the influence of climatic factors on this tree species while comparing it with economically main tree species in Europe – Norway spruce (Picea abies [L.] Karst.). Based on the analysis of 150 increment cores, the radial growth of Sitka spruce was on average 24.2% higher than that of Norway spruce. The highest increments in 52 to 62-year-old stands were achieved in England by both Sitka spruce (8.7 mm) and Norway spruce (7.0 mm). In terms of negative pointer years (NPYs), there was no difference in the number of years with a significantly low increment between the two species at any site. The lowest effect...

High-frequency variation of Norway spruce radial increment [Picea abies (L.) Karst.] and its dependence on various climatic variables was compared in stands across latitudinal and altitudinal transects in southwestern and eastern Germany, Norway, and Finland. The tested variables included local temperature and precipitation, northern hemisphere temperature anomalies, and the climatic teleconnection patterns (North Atlantic Oscillation, East Atlantic, East Atlantic Jet, East Atlantic/West Russia, and Scandinavian patterns). Climatic impact on radial increment increased towards minimum and maximum values of the long-term temperature and precipitation regimes, i.e. trees growing under average conditions respond less strongly to climatic variation. Increment variation was clearly correlated with temperature. Warm Mays promoted radial increments in all regions. If the long-term average temperature sum at a stand was below 1,200–1,300 degree days, above average summer temperature increased radial increment. In regions with more temperate climate, water availability was also a growth-limiting factor. However, in those cases where absolute precipitation sum was clearly related to radial increment variation, its effect was dependent on temperature-induced water stress. The estimated dates of initiation and cessation of growing season and growing season length were not clearly related to annual radial increment. Significant correlations were found between radial increment and climatic teleconnection indices, especially with the winter, May and August North Atlantic Oscillation indices, but it is not easy to find a physiological interpretation for these findings.