Quantitative characteristics of the phases of winter dormancy of conifer species at a site in Central Siberia

Abstract

Traditionally the registration of seasonal changes in plant growth and development has been carried out phenologically, i.e., qualitatively using visual inspection. However, since the process of plant acclimatization to winter dormancy involves reversible biochemical and physiological changes at the level of cells, quantitative methods can be applied to determine the duration and the depth of winter dormancy in perennial plants. We used a method based on detecting thermally induced changes in the zero-level fluorescence (TICZF) on needles from four Siberian coniferous trees. Needles of Picea obovata Ledeb. and Abies sibirica Ledeb. recover from the state of winter dormancy much faster than those of Pinus sibirica Du Tour and Pinus sylvestris L. The photosynthetic apparatus in the needles of A. sibirica may be damaged during the spring period, characterized by unstable weather, when after several days of warm weather, the plants prematurely recover from winter dormancy. We conclude that under conditions of climate warming tree, species like A. sibirica may suffer from severe diebacks due to desiccation caused by premature break of winter dormancy.

Two-Species Forests at the Treeline of Siberian Mountains: An Ecophysiological Perspective under Climate Change

“…All this leads to burns and drying out of needles, which are especially pronounced in fir and prevent the advancement of its seedlings above the treeline [ 13 ]. Siberian pine partially compensates for these factors by increasing the content of carotenoids in needles and by later resumption of photosynthetic activity [ 12 ], which allows Siberian pine seedlings to occupy habitats above the forest boundary.…”

“…Pakharkova et al [ 12 , 13 ] used another approach to foresee how two-species mountain forests may alter their dominant species composition and the treeline position in the West Sayan ridge. The authors measured the content of photosynthetic pigments and the rate of electron transport in needles of codominating Pinus sibirica and Abies sibirica .…”

“…In this study, we continue to extend the approach used in previous studies [ 12 , 13 ] over a different geographic area. The goal of the study was to project the possible alteration at the treeline ecotone in a rather remote and heavily underexplored area of East Sayan under current climate change.…”

Tree species growth response to climate in mixtures of Quercus robur/Quercus petraea and Pinus sylvestris across Europe - a dynamic, sensitive equilibrium

“…Quercus, as ring-porous species, re-establish their vessels from stored carbohydrates early in spring before leaf-unfolding (Morecroft and Roberts 1999). P. sylvestris is anatomically very different and, as conifer species can do photosynthesis during warm periods in winter (Pakharkova et al 2016). Nevertheless, the beginning of cell formation and tree growth for P. sylvestris are also linked to increasing temperatures in spring (e.g.…”