Plants growing higher across Himalaya as climate warms - University of Exeter

Plants are growing higher up mountains across the Himalayan region, new research shows.

The study – led by the University of Exeter – examined the alpine “vegetation line” (the upper limit of continuous plants) in six regions across the Himalaya, from Ladakh, India in the far west of the mountain range, to the extreme east in Bhutan.

From 1999 to 2022, the vegetation line shifted upwards in all six regions – ranging from 1.42 metres per year in Khumbu (home of Mount Everest) to 6.95 metres per year in Manthang, Nepal.

With the climate warming, the team highlighted reduced snow depth as a key potential explanatory driver of these changes.

“The alpine zone is a harsh environment dominated by smaller plants and woody shrubs,” said lead author Ruolin Leng, from Exeter’s Department of Earth and Environmental Sciences.

“But as the climate changes, conditions in the Himalaya are changing in various ways – from temperature shifts and changes in snow cover to the availability of water and nutrients. The Himalaya are warming faster than the global average. A lot of research has focused on the melting of snow and ice, and the implications of this for water supplies on which billions of humans depend. Less research has focussed on plants, particularly the impact of these small alpine plants living at high altitude. But plant communities can also affect the water cycle – so our findings raise important questions that must be investigated.”