abstract: This thesis presents the research concerning the influence of aluminium and copper stress on the surface area as well as on the adsorption energy of water vapour and nitrogen, the size of variable surface charge, the cation exchange capacity, the surface distribution of dissociation constants and the geometry of microporosity of roots of selected monocotyledonous and dicotyledonous plants. The research was carried on the roots of winter rye and winter wheat as well as on the roots of two Fabaceae plants represented by blue lupine and red clover. The hydroponics method was used in the cultivation of the plants. The characteristics of the surface area, adsorption energy and roots microporosity, together with the changes of these characteristics due to the stress factors, were examined using the methods of adsorption-desorption of two adsorbates which were water vapour and nitrogen. The potentiometric titration was used for ionic-exchangeable characteristics (CEC, the surface charge and the distribution of dissociation constants). It was discovered that the apparent specific surface area (determined by water vapour) and the free specific surface area (determined by nitrogen) increased under the sub-lethal and lethal concentrations of aluminium and copper. What is more, the root surface area of dicotyledonous plants increased much more significantly. The surface area grew while the average adsorption energy declined, which was due to a decrease of the fraction of high energy adsorption and an increase of low energy adsorption. The presence of aluminium and the additional application of copper in the culture medium caused a decrease of the total cation exchange capacity and the total surface charge in stressed roots. These changes caused by the stress factors were followed by a decrease of the amount of highly acid surface groups (generating the biggest amount of the surface charge) and an increase of the amount of slightly acid surface groups. More significant changes occurred in the roots of red clover and wheat. The changes of the surface area and the surface charge of roots under the stress caused a significant decrease of the surface charge density. More notable changes occurred in the roots of dicotyledonous plants. The research showed also an influence of the mentioned stress factors on the porosity of the root callus. The average radius and the total volume of the micropores increased under the sub-lethal concentrations of aluminium while the additional application of copper decreased the total volume. The tendencies of change of root surface features under the stress depended on the stress factor (aluminium or copper) and its intensity, as well as on the genetically determined resistance of the examined plants. The most significant changes of the surface occurred in the roots of red clover while a less notable influence of the stress factors was noticed in the roots of winter rye.