It is dormancy or dormancy visible temporary suspension that undergoes the growth of any plant structure containing a meristem. At seed level the term dormancy is used. This dormancy is part of the annual cycle of deciduous or deciduous trees.
Proverb This condition is caused by the low temperatures in autumnalong with shortening the days. Its duration is determined by several factors, such as the species and variety. Inside
Dormancy varies per individual depending on the location of the buds and age.
Roots of climate change
Loose Deciduous trees, such as birch or beech, change color every season. Between autumn and winter the leaves fall and the tree enters a hibernation during which the trunk stops growing. This way they save energy to reactivate themselves in the spring when their leaves emerge again.
Until now, it was believed that the roots had become inactive, meaning that they also stopped activity along with the rest of the tree. New research recently published in Nature Ecology and Evolution shows this the roots continue to grow, without taking any ‘break’.
The study was led by researcher Lorène J. Marchand from the University of Antwerp, with participation from CREAF and CSIC, and the results suggest that forest land is a carbon sink with greater capacity than previously thought, because it accumulates carbon all year round. not just when the leaves are performing photosynthesis and the tree is most active. Furthermore, it represents a change in the perception of how deciduous trees adapt to climate change in the future.
«The results show that theThe above-ground part and the underground part of the tree follow separate calendarsThat’s why they prioritize underground growth during winter and aerial growth at the beginning of spring,” explains Paolo Zuccarini, CREAF researcher and co-author of the study. This decoupling could be a strategic advantage, because in winter the roots store reserves of carbohydrates and other nitrogen-rich substances, such as proteins or amino acids, while the rest of the tree is inactive. So when they ‘wake up’, they have enough food to make the leaves appear and reactivate photosynthesis, which is what happens. is essential for the growth of the trunk and branches.
“It’s like having building blocks ready to use in the spring The priority is to generate leaves to resume photosynthesis“continues Zuccarini. This surprising study was conducted with four tree species in different temperate forests in Spain, Belgium and Norway. A total of 330 trees, both adult and 3-year-old seedlings, of common beech (Fagus sylvatica), birch (Hanging birch), common oak (Quercus robur) and aspen (The people trembled).
1000 samples of thick roots of more than 2 millimeters were collected, as this is the case from this measurement when the root undergoes lignificationknown as xylogenesis. “The data shows that thick roots maintain their activity even at soil temperatures below 3°C. This refutes the belief that cold stops underground growth,” explains Lorène J. Marchand, the lead author of the study.
Soil nutrients
Another aspect that stands out is that the value of forest land as a carbon sink could be greater than previously thought, as research shows deciduous trees repair it all year round. According to researchers, trees store carbon in their structure and use it for the growth of wood in the roots and trunk.
This stored carbon is very stable because it is integrated into plant tissues in the form of lignified biomass, consisting of cellulose, hemicellulose and lignin. “In fact, thick roots contribute significantly to the carbon sink activity of trees to the 20% to 30% of a tree’s total biomassbecause of its high density,” Zuccarini adds.
According to the authors, the results indicate that root growth does not stop in winter, and that is indeed the case the natural clock of the roots could be less influenced by external signals such as temperature or light, and more controlled by internal signals, such as the tree’s carbon reserves, “as opposed to the above-ground part that is more subject to the external climate,” says Josep Peñuelas, CSIC researcher at CREAF and co-author of the research. . This could help trees adapt to changing climate conditions, such as warmer springs, premature snowmelt or irregular rainfall, preparing roots in winter for use in spring even as conditions change.
The results indicate that Root growth does not stop in winter and therefore that the roots’ natural clock could be less influenced by external signals such as temperature or light. This international study was led by Lorène J. Marchand and Matteo Campioli from the PLECO group at the University of Antwerp, together with. Ghent University in Belgium. Several European entities also participated, such as CREAF and CSIC in Spain, the Slovenian Forestry Institute in Slovenia, the University of Umea in Sweden, the Bioeconomy Research Institute in Norway and the Swiss Federal Forestry Research Institute Snow and Landscape.