Mountain forests are disappearing at an alarming rate, threatening nature in some of the planet's most biologically rich areas, warn scientists.
More than 7% of mountain forests have vanished since 2000, an area larger than Texas, researchers have discovered from studying satellite data.
Much of that loss was in tropical areas that are key nature habitats, putting threatened species in greater danger.
Logging and wildfires caused most of the loss, followed by agriculture.
The study led by Leeds University and the Southern University of Science and Technology in China is published in the journal One Earth.
Mountains areas are home to more than 85% of the world's birds, mammals, and amphibians, with forested mountain areas being particularly important habitats for nature and wildlife, say the researchers.
Their relative inaccessibility once protected them but they have been increasingly deforested this century as lower-lying areas have become depleted or gained protection.
The researchers tracked changes in mountain tree cover across the world between 2001 and 2018, comparing different types of forests at different altitudes, in order to study how the losses affected nature.
We are losing mountain forests more quickly than before, they noted, with the speed of loss accelerating by 50% between 2010 and 2018 compared with the period between 2001 and 2009.
The most significant losses were in Asia, South America, Africa, Europe, and Australia. The researchers singled out the expansion of farming into highland areas of Southeast Asia as a major cause of the acceleration.
Protected forests fared better, but the researchers warned it was vital that tree cover was preserved over large enough areas to let species to roam naturally.
They also stressed that it was important to take people living in mountain forest areas into account.
Any new conservation measures "need to reconcile the need for enhanced forest protection with ensuring food production and human wellbeing," they said. (BBC)