Helping prevent full scale Mongol invasions in India, the Himalayas like any other mountain range, have deterred men from crossing it since its creation. Evolving at high altitudes cutting it off from human activities, the sensitive regional ecosystem responds dramatically to new anthropogenic developments and climate change. An essential biodiversity hotspot in these regions are the mountain forests, which used to cover over 1.1 billion hectares of the planet in 2000. But as per a study published in the Cell Press journal One Earth, we have lost over about 78.1 million hectares of these forests by 2018.
The Food and Agriculture Organisation defines mountain forests as “forests on land with an elevation of 2,500 m above sea level or higher, irrespective of slope, or on land with an elevation of 300 to 2,500 m and a slope with sharp changes in elevation within a short distance.” They are the natural habitat to about 85 percent of the world’s mammals, birds, and amphibians. And that’s why it becomes a major concern when the study mentions that more than 40 percent of the regions lost are those which serve as “tropical biodiversity hotspots” providing a safe haven to rare and endangered species of flora and fauna.
The study pointed out that the major chunk was taken out by “commercial forestry (42 percent), followed by wildfires (29 percent), shifting cultivation (15 percent), and commodity agriculture (10 percent).” But it also mentioned that these causes and the degree of these causes may vary from one region to another. About 38.9 million hectares of mountain forests were lost in Asia– mostly in Russia – which is more than half of the global total. It’s followed by South America, Africa, Europe, and Australia.
“The drivers are different for different regions,” Dr. Zhenzong Zeng, co-author of the study, told AFP. He explained that the forests found in higher latitudes are more affected by wildfires, caused due to higher temperatures and low rainfall. For the Southeast Asian mountain forests, in particular, he claimed that there needs to be a control over commodity farming where people need “to grow corn to feed their chickens” instead of rubber and palm trees. He also warned against using fossil fuels since it’s only accelerating the process of global warming.
Increasing temperatures force the wildlife species to move further uphill in search for a cooler climate. But they can only move up to a certain point, after which there won’t be any place to rehabilitate. This process of gradual biodiversity loss is known as “escalator to extinction”. As for the flora, the alpine vegetation of the mountains isn’t highly adaptive, thereby losing ground to the invasive species much more adaptive to the changing climate.
One way to preserve these sensitive ecosystems, as suggested by the study, is to increase the land area under protection or create new protected areas covering the biodiversity hotspots. This can help reduce the rate of loss of mountain forest lands. The study also mentioned that the net rate of mountain forest loss from 2000 to 2018 has been limited to 0.31 percent per year due to tree cover regrowth experienced by the regions.