Physiological reaction and energy accumulation of dominant plant species in fir-beech ecosystems affected by air pollution

anglais. Physiological reaction and energy accumulation of assimilatory organs of 4 dominant plant species were studied in fir-beech ecosystems (80-100-year-old stand) and parallel clear-cut area (10-year-old stand) in locality Hliníky situated in the buffer zone of the Slovenský raj National Park. Studied ecosystems are located on the area affected by human activities. The achieved results showed that the influence of stand climate and habitat conditions differentiated the measured characteristics. Significantly higher photosynthesis was observed in assimilatory organs of F. sylvatica, R. idaeus, D. filix-mas and V. myrtillus species in the fir-beech stand (range 5.79–16.10 μmol CO2 m–2 s–1) compared to the clear-cut area (range 4.54–12.89 μmol CO2 m–2 s–1). V. myrtillus and F. sylvatica species reacted sensitively with significantly lower values of stomatal conductance (0.24, respectively 0.26 mol m–2 s–1) in clear-cut area

R. idaeus and D. filix-mas showed significantly lower values (0.57, respectively 0.29 mol m–2 s–1) in the fir-beech stand. Reduction of Fv/Fm under physiological limit was found for F. sylvatica species growing in clear-cut area, where the file of habitat conditions was not probably optimal. Energy content in phytomass of studied plant species varied from 18,511 J g–1 (R. idaeus) to 20,551 J g–1 (V. myrtillus). Significantly higher was only the mean value found for D. filix-mas species growing in the fir-beech stand (19,049 J g–1) compared to the clear-cut area (18,561 J g–1).