Growth parameters and leaf functional traits of birch trees regenerating at the ash dump of the Verkhnetagilskaya power station

Abstract

Growth parameters and leaf functional traits were studied in Betula pendula Roth and Betula pubescens Ehrh. naturally regenerating at the ash dump of the Verkhnetagilskaya power station (Sverdlovsk region), as well as in the forest stand adjacent to the ash dump. The growth parameters (trunk height and diameter) of the trees at the ash substrate and in the forest cenosis had close values, and the distribution of birches according to the relative height of the trunk indicated their sustainable development at the ash dump. Changes in leaf parameters manifested in a significant increase in thickness and a decrease in the bulk density of the leaf blade were found in the trees growing at the ash dump. Leaf size, shape, and specific mass area (LMA) did not depend on the growing conditions of the trees. It was concluded that the adaptation of birch trees to nitrogen deficiency is based on changes in leaf parameters, aimed at maintaining the rate of photosynthesis providing sustainable growth of trees in unfavorable edaphic conditions.