The content of nutrients, lignin and cellulose in plants and lichens in the forest-tundra ecotone of the Khibiny mountain massif

Abstract

The results of studies of the chemical composition of plants and lichens in the altitude gradient on the slope of Yumechorr of the Khibiny mountain massif (Murmansk region) are presented. The species specificity of the accumulation of macro- and microelements by the assimilating organs of plants and lichens in the in the main altitude zones is shown. The leaves of Betula pubescens and Vaccinium myrtillus are the most rich of elements of mineral nutrition. Lichens are characterized by a low content of N, Ca, K, P, Mg, S, as well as Zn and Mn and high - Fe, Cu, Ni. In spruce and pine needles, similar patterns of the distribution of elements by age classes were revealed. Changes in the content of nitrogen, mineral elements, secondary metabolites in the altitude gradient in the assimilating organs of plants and lichens, during the transition from the forest belt to the mountain forest, have been established. It has been established that with increasing growth height, the N content increases in Pinus sylvestris needles, in the leaves of Arctostaphyllos uva-ursi, in the leaves of the current year Empetrum hermaphroditum. Plants growing in the mountain tundra and forest tundra are characterized by a high content of K. The Zn content also increases with increasing absolute height in the conifers/leaves of P. sylvestris, B. pubescens, V. uliginosum. During the transition from the forest belt to the mountain tundra, the content of Ca and Mg decreases in plant leaves. In the leaves of E. hermaphroditum, minimal concentrations of Mn were also detected in the mountain tundra. The content of lignin and cellulose in the leaves of shrubs, with the exception of V. myrtillus, in the belt of coniferous forests is lower than in the belt of birch forests and tundra. The content of lignin in the leaves of B. nana and B. pubescens increases, and cellulose practically does not change with an increase in absolute height in the Khibiny Mountains. Accumulation of lignin is observed in needles of P.sylvestris in the belt of birch woodlands.