Research Highlights: For the first time, the Pinus sibirica Du Tour and Abies sibirica L. conifer forest at the West Sayan ridge timberline has been explored to reveal which species is likely to react to climate change and a shift of the timberline. Such a shift may modify the ecological functions of the forests. Background and Objectives: Long-term climate change has become obvious in the mountains of southern Siberia. Specifically, a half-century rise in annual mean temperatures has been observed, while precipitation remains unchanged. Trees growing at the timberline are likely to strongly react to climate alterations. The objective was to estimate which of the two species sharing the same habitat would benefit from climate alteration and shifting of the timberline. Materials and Methods: At several altitudes (from 1413 to 1724 m a.s.l.), samples of P. sibirica and A. sibirica needles have been collected and contents of chlorophyll a and b as well as carotenoids were measured in June 2019. The temperature of needles of the two species was measured in both cloudy and sunny weather conditions. Results: The studied species have been shown to have different patterns of pigment variations with the growth of altitude. The decline of chlorophylls and carotenoids was more pronounced in P. sibirica (ratio at timberline ca. 2.2) than in A. sibirica (ratio ca. 3.1). Accordingly, the electron transport rate decreased more strongly in P. sibirica at the timberline (ca. 37.2 μmol of electrons/m⁻² s⁻¹) than in A. sibirica (56.9 μmol of electrons/m⁻² s⁻¹). The temperatures of needles in both cloudy and sunny weather were higher in A. sibirica (10.5 and 43.3 °C, respectively) than in P. sibirica (3.8 and 24.2 °C, respectively). Conclusions: The considered physiological and ecological traits show that P. sibirica is better protected from higher-altitude hazards (excess insolation, rise of temperature etc.) than A. sibirica. P. sibirica may be therefore a more likely winner than A. sibirica in the movement of the mountain timberline under climate warming in the area.

Differences in terms of depth of dormancy have been revealed in the provenace trial of Scots pine based on an analysis of parameters of the zero fluorescence level, as well as the content of chlorophylls and abscisic acid, which corresponds to the results of studying the pine-needle morphological traits and phenological observations. Trees of the southern climatype different in terms of needle morphological traits and the length of phenological stages are characterized by a deeper dormancy than those of the northern climatype. It is assumed that, due to climate change, northern climatypes would be more vulnerable during winter-spring thaws, which were not typical of these regions in former times.

Heavy metals are potentially toxic to human life and the environment. Metal toxicity depends on chemical associations in soils. For this reason, determining the chemical form of a metal in soils is important to evaluate its mobility and the potential accumulation. The aim of this examination is to evaluate the accumulation potential ofPetunia x hybridaas a flower crop for three metals, namely, copper (Cu), lead (Pb), and nickel (Ni). Trace metals (Zn, Cu, and Pb) in the soils were partitioned by a sequential extraction procedure into H₂O extractable (F1), 1 M CH₃COONa extractable (F2). Chemical fractionation showed that F1 and F2 fraction of the metals were near 1% and residue was the dominant form for Zn, Cu, and Pb in all samples. Using fluorescence method allowed us to estimate condition of the plants by adding metals. As result of plant and soil analysis, we can conclude thatPetuniahas Cu, Zn, and Ni tolerance and accumulation. Therefore,Petuniahas the potential to serve as a model species for developing herbaceous, ornamental plants for phytoremediation.