Some patterns of the accumulation of trace elements in the leaves of linden (Tilia cordata Mill.) and birch (Betula alba L.)
A.V. Gorbunov, D.B. Petrenko, A.A. Dronova
Section: Chemistry of natural environments and objects
The purpose of the work: to study the patterns of background accumulation of trace elements during the spring-summer-autumn season in the vegetative organs (leaves) of the heart-shaped linden (Tilia cordata Mill.) and white birch (Betula alba L.). Samples were taken on the territory of the Main Botanical Garden of the Russian Academy of Sciences during one season of 2018 from the same tree with an interval of 10–12 days, starting from the opening of the bud (end of April) right up to the time of leaf fall. Soil samples were also taken from birch and linden growing areas. The samples were analyzed in the laboratory of Chemical analytical methods of the GIN RAS using X-ray fluorescence analysis (XRF), instrumental neutron activation analysis (INАA) and atomic absorption spectrometry of cold vapor (AA). The concentration of trace elements in the selected soil samples corresponds to the concept of “background” contents. Two types of trace elements’ distribution in linden and birch leaves during the season have been revealed. The first type is a uniform accumulation of trace elements with a maximum at the end of the season (Na, Ca, Cr, Fe, Co, Br, Sb, La). The second type of distribution is characterized by a maximum concentration of trace elements in the middle of the season with a decrease in concentration by the time of leaf fall (K, As, Zn, Cd, Pb). It should be noted that the range of changes in the concentration of trace elements during the season in both cases can reach 10–15 times. We recommend to take samples of vegetation (leaves) as soon as possible in the middle of the summer season, and to use samples taken at the same time in the same area as “background”.