A new study suggests that climate change will alter mountain ecosystems around the world.
Photo by Bob Berwyn. From psmag.com
A new study from an international team of researchers indicates that climate change poses a direct threat to fragile mountain habitats, affecting both glaciers and the proliferation of high-altitude species. The international study, which examined seven of the world’s major mountain regions, which are warming twice as fast as the global average, found that higher temperatures are speeding up microbial activity, and leading to fundamental changes that could displace some plant life and dramatically alter the habitat of others.
”Our results, which come from an extensive study of elevation gradients across seven mountain regions of the world—including Japan, British Columbia, New Zealand, Patagonia, Colorado, Australia, and Europe—suggest that future climate warming will substantially alter the way that these sensitive ecosystems function,” said Professor Richard Bardgett, an ecologist from the University of Manchester and one of the study’s authors. (The University of Manchester)
Scientists from 10 universities studied areas above and below the alpine tree line in each region, and found that decreasing elevation provided a “surrogate” indicator of climate warming. For example, the researchers found that the warmer temperatures of lower altitudes carried a corresponding and consistent increase in the availability of nitrogen from the soil for plant growth, but not of phosphates, suggesting that global warming could radically disrupt the delicate balance of mountain ecosystems.
The study, published in the journal Nature, also predicted that temperatures in mountainous regions will rise rapidly by the end of the century, meaning that by 2100 the temperature at a given altitude now is likely to be reached 300 meters higher.
”A clear message from our findings is that climate warming could change the functional properties of mountain ecosystems and potentially create a disequilibrium, or mismatch, between plants and soils in high mountain areas,” said Prof. Bardgett. “Not only could this have far reaching consequences for biogeochemical cycles but it could also affect mountain biodiversity.” (The University of Manchester)
In addition, the researchers observed that higher temperatures were linked to other changes in soil quality, including the quantity of organic matter and the soil’s microbial composition. They noted that these observations were not completely dependent on the effect of the alpine tree line, meaning that the effects of warming on ecosystems would occur irrespective of changes in the migration of tree growth to higher elevations due to warmer temperatures. The study’s conclusions are especially convincing because the team made the same findings at each study sites.
“We’re seeing these things become unlinked and trying to understand the consequences,” said Prof. Nathan Sanders, an ecologist at the University of Vermont. “We studied places with different geology, different plant communities, and yet we saw the same thing over and over again.” (Pacific Standard)
Such dramatic changes over a relatively short period of time could have an ecological domino affect on plant communities and mountain ecosystems, affecting other plant species and, consequently, the fauna that they support, such as insects and birds.
“We can assume there might be implications for biodiversity. One striking observation was the clear upward migration of species. This might affect biodiversity at higher elevation,” said Prof. Michael Bahn, a climate scientist at the University of Innsbruck in Austria. “Plants adapted to lower elevations will grow faster and could outcompete rare plants higher up.” (Pacific Standard)
The Dachstein glacier in Austria has retreated by hundreds of meters in just a few decades.
Photo by Bob Berwyn. From psmag.com
Climate change is not only affecting biodiversity, but also having an impact at the geological level, markedly altering mountain landscapes. Massive landslides have been recorded in the Alps in areas where glaciers and permafrost have melted so rapidly that vegetation has not had time to grow and to protect against erosion.
“Humanity relies on mountains,” observed Prof. Sanders. “We found in all these places that temperature change drives many other kinds of change, potentially disturbing biodiversity, and that could have a profound effect on the ecosystem services mountains provide to people—like clean water.” (EurekAlert)