The role of environmental factors in ozone uptake of Pinus mugo Turra

Özet

Montane forests in the High Tatra Mountains are exposed to high ambient ozone (O3) concentrations that mayadversely affect the physiological processes and health of plants. This study presents the modelled results of thephytotoxic ozone dose (POD) for dwarf mountain pine (P. mugo) in 2016. POD metrics were calculated using thedeposition model DO3SE, with O3concentration and meteorological data measured in three altitudinal zones. Inaddition, maximal stomatal conductance (Gmax) derived from gasometricfield measurement in local conditionswas included in the model. Field measurements confirmed the robust performance of the DO3SE model forstomatal conductance (Gsto). The site-specific stomatal conductance response model was largely congruent withaverage values estimated by DO3SE, though differences in temporal Gstodistribution were observed. We de-termined a moderate limitation of O3uptake due to environmental factors (fENVI) such as air temperature andrelative humidity, solar radiation, and soil water availability. It appears that Gmaxis more relevant for annualPOD than fENVIin the temperate mountain forest. The results indicate a high level of POD and O3uptake byP.mugoin the High Tatra Mountains, which corresponds with the O3-induced visible injury symptoms observed.We also identified visible O3injury inP. mugoneedles, which was more prevalent among the two-year oldneedles than younger individuals.