Comparative study of two spruce species in a polluted mountainous region

Tolerance to pollution and climatic conditions are compared in Colorado blue spruce (Picea pungens) and Norway spruce (Picea abies) from two adjacent stands in the Krusne Hory Mountains, Czech Republic. The anatomy of needles was described quantitatively using image analysis, and the content of photosynthetic pigments, accumulation of lignin and phenolics, and reflective properties of needles of the two species were compared. Anatomical and morphological adaptations of Colorado blue spruce needles (i.e. lower needle surface area: volume ratio) suggested greater potential resistance to air pollution than Norway spruce. However, no difference in the degree of cell damage was recorded. Although concentrations of chlorophyll, carotenoids and their ratios were similar, lignification and phenolic accumulation was greater in Norway spruce. The red edge inflection point, as well as stress indices and reflectance ratios, suggested an age-dependent increase in needle damage of both species. Needles of young Colorado blue spruce and Norway spruce exhibit the same degree of damage in response to air pollutants.