Abstract
The needles of Larix decidua Mili. and Larix leptolepis showed different pattern of seasonal chlorophyll variability, the level of pigments in L. decidua was more influenced by zinc-plant emissions than that in L. leptolepis. The concentrations of chlorophyll a and b and their changes were markedly different from those estimated for the non-deciduous species. The seasonal variability of acidity of aqueous homogenates of the consdered larch needles appeared to be less characterisitic for the species and also for the pollution influence than the changes in buffer capacity.