Minimization of Photosynthesis due to Air Pollution

In this work the leaf structure of Phlomis fruticosa and Urginea maritima from a strongly perturbated, by means of air pollution, phryganic ecosystem in Attica (Greece) was studied in comparison to the leaf structure of the same plants from a similar phryganic ecosystem free of air pollutants. The first, light microscope detected, detrimental effects of air pollutants refer to chloroplasts. The latter are fewer and smaller in the leaves of the affected plants. A second effect of air pollution on the P. fruticosa leaves is the shape of the chloroplast containing mesophyll cells, which appear to be more irregular than in normal plants. Besides, leaves of U. maritima exhibit colorless areas, that is areas without chloroplasts, where the mesophyll cell layers have been practically reduced. In other words the leaf of U. maritima shows abundant colorless constricted areas in its blade. It is reasonable to presume that the above effects on chloroplasts leads to the minimization of photosynthesis. Therefore, our results justify the low primary production of the most air polluted ecosystems as well as the lower biomass estimations in these, available in the literature.