Functional adaptation of Quercus robur L. and Cercidiphyllum japonicum Siebold et Zucc. in the urban landscapes of Lviv

Abstract

The general trends in the purity changes of the environment in connection with the urbanistic technogenesis were analyzed on the example of the largest city of Western Ukraine – Lviv – and its outskirts, Dublyany. The characteristic changes of some parameters of the main environmental factors – transformed ecosystems, including biogeochemical properties of edaphotope and pollution by heavy metals are described. Urbanization leads to a tendency of parkerising, alkalinization and significant measure of green zone soil contamination with heavy metals. The increase of the complex pressure of urban anthropogenic environment on vegetation is revealed and current changes of the chemical composition of dry matter of leaves of trees in terms of heavy metal content and structure-energy metabolites are analyzed. A significant accumulation of some chemical elements in the assimilation system of Quercus robur L. and Cercidiphyllum japonicum Siebold et Zucc. was found, their species-specific features of ash accumulative ability were revealed. Cercidiphyllum japonicum is proved to be a promising and effective, in terms of cleaning the environment from man-made pollution, decorative plant in the green belt of cities in the regions of Roztochchia and Pasmove Pobuzhya. Under the influence of edaphotope transformation and pollution in the assimilation bodies of woody plants some structural and metabolic changes occur to adapt to the new to their species environment. Oak as autochthonous species, has signs of stability of the metabolic system of assimilation to the urban genic changes. Cercidiphyllum’s structure demonstrates plasticity of dry matter of leaves, designed to adapt to the new environment acclimatization of exotic species, and thus performs an effective metal storage function in a green area of the city.