Comparative studies of the leaf morphology and structure of white ash Fraxinus americana L. and London plane tree Platanus acerifolia Willd growing in polluted area

The leaf blades of white ash Fraxinus americana L. and London plane tree Platanus acerifolia Willd. growing in heavy polluted industrial areas were studied for morphological and anatomical changes developed under the influence of industrial contamination. The aim of the investigation was to determine and compare the influences of air polluted with SO2, NxOx, Pb, As, Zn, Cu etc. on the morphology and the structure of the leaves of these deciduous trees. Both species are tolerant to environmental changes but with different environmental characteristics and tolerances and they are widely used for planting. Under polluted conditions, the trees strengthened the anatomic xeromorphic characteristics of their leaf structures, which gave them the opportunity to mitigate the stressful conditions of the environment. The observed responses are regarded as adaptive and compensative to the adverse effects of air pollution.