Mountainous regions around the world are under serious threat due to climate change , a phenomenon primarily driven by human activity. The impact of this global problem could radically alter fragile mountain ecosystems, alterations already being documented in several scientific studies. An international group of researchers, including an expert from the University of Manchester, has highlighted how these effects could disrupt the balance between plants, soil, and other critical elements of high mountain environments.
Climate change and mountain ecosystems: the study
Ecologist and professor Richard Bardgett of the University of Manchester, co-author of the study that explored the effects of climate change in various mountain regions, emphasizes that the message is clear: global warming is altering the essential properties of mountain ecosystems . These changes could generate a profound imbalance between plants and soils, affecting high-latitude and high-altitude areas.
The research team worked with data collected from seven of the world's major mountain regions, including Japan, New Zealand, Patagonia, and the Alps, among others. One of the most significant findings was the increased availability of nitrogen in the soil as temperatures rise. This could disrupt the natural functioning of these ecosystems, severely impacting plant growth.
Another important finding was that phosphorus availability to plants appears unaffected by these changes in elevation, leading to a disruption in the delicate nitrogen-phosphorus balance . This balance is crucial for plant development, and its imbalance could have devastating effects in high mountain areas.
Consequences of temperature changes for soil and plants
In addition to the alteration of nutrients, the study revealed that warmer temperatures are also linked to changes in other aspects of the soil, such as the amount of organic matter and the composition of the microbial community. This directly affects the soil's ability to support plant life.
Mountain areas are particularly sensitive to these changes due to their geography and altitude. As temperatures rise, glacier melt and snow cover decrease, the amount of water flowing down rivers is reduced, affecting both the ecosystem and the human communities that depend on these resources.
“Mountain areas cover a significant portion of the Earth’s land surface and are particularly vulnerable to climate change. Our study reveals that mountain ecosystems will change substantially if temperatures continue to rise at this rate,” Bardgett noted.
Climate change hotspots in mountain areas
By studying the seven mountain regions, researchers identified several biodiversity hotspots. Mountains harbor a wealth of biological diversity, making them “biodiversity towers .” However, as the climate changes, so do the living conditions for various species, many of which are already endangered. For example, the capercaillie, a species typical of subalpine forests, is already facing a drastic population decline due to these combined effects.
Snow and precipitation patterns
In high mountain regions, decreased snowfall and reduced precipitation have devastating effects on ecosystems that depend on water from glaciers and seasonal snow. According to recent studies in the Alps and Pyrenees, snow cover at lower altitudes could decrease by up to 80% by the end of the 21st century.
This decline affects winter tourism, an economic mainstay in many areas, but also threatens the survival of species that depend on snow as habitat or shelter. In addition, the retreat of glaciers, as observed on Kilimanjaro or the Peruvian Andes, is already affecting water flow patterns.
As global temperatures rise, the water balance is not only affecting flora and fauna, but also human activities. In places like the Pyrenees, rivers originating in the mountains supply large areas, and the reduction in flow affects both agricultural and hydroelectric production, potentially triggering conflicts over this increasingly scarce resource.
Mountains as indicators of global change
Mountains have always been early indicators of global change, not only due to glacial retreat but also because they serve as refuges for endemic species highly sensitive to changes in temperature and precipitation. Some plant and animal species could adapt by migrating to higher altitudes, but for many, this is not a viable option.
An example of this is the upward movement of the forest edge. While upward movements have been recorded in alpine trees such as juniper and broom in recent decades, other species cannot adapt as well and face extinction. These phenomena are also influencing high mountain farming and livestock activity, affecting the economy of many regions.
Adaptation of human communities
The challenge is not only biological or ecological, but also social. Communities that have lived in these regions for centuries face an uncertain future. The local economy, based on agriculture, livestock and tourism, may collapse if climate change adaptation strategies are not developed.
Population displacements are already being observed in some mountainous regions due to the loss of water sources and reduced agricultural productivity. In some places, the increased risk of wildfires adds another layer of complexity to the existing problems.
What can we do to mitigate these effects?
Given these scenarios, mitigating climate change in mountain areas requires the adoption of new public policies. According to experts gathered at the 2019 High Mountain Summit , it is essential to promote international cooperation to manage mountain resources and develop new adaptation strategies.
In parallel, it is necessary to promote the reforestation of degraded areas, use water more efficiently, and restore mountain ecosystems with practices that respect biodiversity. Reducing greenhouse gas emissions is, of course, one of the most urgent measures to prevent irreversible damage.
Mountains remain a haven of biodiversity and a crucial resource for millions of people. Responsible action is urgently needed to ensure that they continue to play their role in climate stability and water availability in the future.