Experts observed the striking trend on the spectacular Kuznetsky Alatau mountain ridge in southern Siberia. Picture: Ilya Petrov

A rise in air temperature from climate change is leading to birch trees growing at higher altitudes than previously.

The tree line is moving up mountains at a rate of half a metre a year, say researchers from Krasnoyarsk Science Centre, part of the Siberian Branch of the Russian Academy of Sciences.

Experts observed the trend on the Kuznetsky Alatau mountain ridge in southern Siberia.



Geographical location of the studied sites (1 − test plots, 2 − rivers and lakes, 3 − dark needle conifer stands). Picture: Ilya Petrov

‘The rise of average air temperatures leads to an increase in the number of birch trees, and the trees’ growing area is enlarging too, and moves towards the mountains,’ said the centre.

Specifically, traditional Russian birch trees are now invading the mountain tundra climate zone, which was previously too harsh for birches.

‘If global warming continues, in the future the forests will occupy the territory of what is today the mountain tundra climate zone.’

They noted a marked trend since the 1970s.



Ilya Petrov: ‘If global warming continues, in the future the forests will occupy the territory of what is today the mountain tundra climate zone.’ Pictures: Ilya Petrov

‘Due to global warming, the birch trees are occupying heights where conditions are becoming more and more comfortable for their growth,’ said co-author of the research Dr Ilya Petrov, senior scientist at the Sukachev Forest Research Institute.

The results of the research were published in the digest BIO Web of Conferences.

The research did not cover whether birch trees are also venturing northwards as the climate warms in higher latitudes.