More than 85% of the world’s bird, mammal and amphibian species live in mountains, mainly in forest habitats, but the researchers report in the journal. one land On March 17th these forests are disappearing at an accelerated rate. Globally, we have lost 78.1 million hectares (7.1%) of mountain forests since 2000 – an area larger than the state of Texas. Much of the loss has occurred in tropical biodiversity hotspots, adding pressure to threatened species.
Although their rugged location once protected mountain forests from deforestation, they have been increasingly exploited since the turn of the 21st century.street century as lowland areas became depleted or protected. A team of scientists led by Xinyue He (xinyue_he), Dominic Spracklen and Joseph Holden from the University of Leeds in the UK, and Zhenzhong Zeng from the Southern University of Science and Technology in China, wanted to investigate the extent and global distribution of mountain forests. Loss.
To do this, the team tracked changes in mountain forests on an annual basis from 2001 to 2018. They quantified losses and gains in tree cover, estimated the rate at which change was occurring, compared different elevations and types of mountain forests — boreal, temperate, tropical — and explored the effects of forest loss. This is on biodiversity.
“Knowing the dynamics of forest loss along elevation gradients worldwide is critical to understanding how and where available forest area for forest species will change as they shift in response to warming,” the authors wrote.
Logging was the biggest driver of mountain forest loss overall (42%), followed by wildfires (29%), shifting or “slash-and-burn” cultivation (15%), and permanent or semi-permanent agriculture (10%), although important These various factors vary from region to region. Significant loss occurred in Asia, South America, Africa, Europe and Australia, but not in North America and Oceania.
Alarmingly, the rate of loss of mountain forests appears to be accelerating: the annual rate of loss increased by 50% from 2001-2009 to 2010-2018, when we lost approximately 5.2 million hectares of mountain forests annually. The authors write that this acceleration is probably due in large part to rapid agricultural expansion in the highland regions of mainland Southeast Asia, as well as increased logging in mountain forests either because lowland forests are depleted or because lowland forests have become protected.
Tropical montane forests experienced the greatest loss – 42% of the global total – and the fastest rate of acceleration, but also had a faster rate of growth compared to montane forests in temperate and boreal regions. Overall, the researchers noted some signs of regrowth of tree cover in 23% of the areas that lost their forests.
Protected areas have experienced less forest loss than unprotected areas, but researchers warn this may not be enough to preserve threatened species. “With respect to sensitive species in biodiversity hotspots, the critical issue extends well beyond simply preventing forest loss,” the authors wrote. “We must also maintain the integrity of forests in areas large enough to allow natural movements and enough space for species to breed.”
The authors also stress the importance of considering human livelihoods and well-being when developing forest protection strategies and interventions. “Any new measures to protect mountain forests must adapt to local conditions and contexts and need to reconcile the need for enhanced forest protection with ensuring food production and human well-being.”
This research was supported by the Southern University of Science and Technology, the University of Leeds, and the National Natural Science Foundation of China.