Jake Slobe | February 1, 2017
Mountain regions of the world are under direct threat from human-induced climate change which could radically alter their fragile habitats, warn an international team of researchers.
The international study, which spanned seven major mountain regions of the world, revealed that decreasing elevation – descending a mountainside to warmer levels –consistently increased the availability of nitrogen from the soil for plant growth, meaning that future climate warming could disrupt the way that fragile mountain ecosystems function.
The researchers also found that the balance of nitrogen to phosphorus availability in plant leaves was very similar across the seven regions at high elevations, but diverged greatly across regions at lower elevations. This means that as temperatures become warmer with climate change, the crucial balance between these nutrients that sustain plant growth could be radically altered in higher mountain areas.
They also found that increasing temperature and its consequences for plant nutrition were linked to other changes in the soil, including amounts of organic matter and the make-up of the soil microbial community.
These changes were partly independent of any effect of the alpine tree line, meaning that effects of warming on ecosystem properties will occur irrespective of whatever shifts occur in the migration of trees up-slope due to higher temperatures.
Rather than use short-term experiments, the research team used gradients of elevation in each mountain region spanning both above and below the alpine tree line.