ALUMINIUM CONCENTRATION IN PLANTS DEPENDING ON SOIL CONTAMINATION WITH CADMIUM

The aim of the study has been to determine the effect of soil contamination with cadmium (10, 20, 30 and 40 mg Cd.ha(-1) soil) on the concentration of aluminium in aboveground parts and roots of oats, maize, yellow lupine and radish. In order to neutralise cadmium, the following neutralising agents were introduced to soil: compost, brown coal, lime and bentonite. Apart from the plant species and type of organs, other factors which largely affected the concentration of aluminium were a rate of cadmium and type of a neutralising substance. Roots contained much more aluminium than aboveground parts of plants. The highest levels of aluminium were found in roots of yellow lupine and maize whereas the smallest concentrations of this metal were determined in grain and roots of oats. Soil contamination with cadmium caused bigger changes in the concentration of aluminium in aboveground parts of plants than in their roots, especially in the case of maize and yellow lupine. Cadmium applied at 20 mg (maize and yellow lupine roots) or 40 mg Cd.ha(-1) soil (aboveground parts of maize and yellow lupine) caused increased levels of cadmium in plant tissues. Any further increase in the rates of the pollutant caused depression in the content of aluminium in roots of the above crops. In the case of aboveground parts and roots of radish and grain of oats, less aluminium was observed in all cadmium contaminated objects. The range of effects produced by the test neutralising substances on the concentration of aluminium was varied. The neutralising agents tended to depress the content of aluminium in plant tissues. Brown coal, bentonite and lime caused larger changes in the content of aluminium than compost. The concentration of aluminium was correlated with yields of the crops. For most of the plants, these correlations were negative in the case of aboveground parts (except radish) and positive in roots (except yellow lupine). The concentration of aluminium in particular plant organs was correlated with a number of macro- and microelements, with the correlations being usually positive for manganese, iron, cobalt, lithium, copper and zinc but negative for sulphur and boron.