The presence of horses, bison or reindeer in polar regions can slow the rate of permafrost, helping to combat climate change.
Arctic permafrost is melting rapidly. As a result, bacteria begin to break down the trapped organic carbon and release large amounts of methane and CO2 into the atmosphere, exacerbating climate change. A new study, published in Scientific Reports on March 17, shows that large herds of ungulates can help slow this effect.
Experts from the German University of Hamburg conducted experiments on herds of bison, horses and reindeer in the Pleistocene Park in the town of Chersky in northeastern Russia. These ungulates were moved to the area over 20 years ago in an attempt to monitor their impact on the permafrost below.
In winter, the permafrost in Chersky is only -10 ° C, much “warmer” than the air temperature above (perhaps down to -40 ° C). This is because thick snow forms a layer separating the ground from the air, causing the permafrost below to have a higher temperature.
The team found that the presence of herds of ungulates compressed and dispersed the surface snow. More precisely, for every 100 animals living in an area of one square kilometer, the average height of the snow cover is halved. This significantly reduces its insulating effect and thus improves the freezing capacity of permafrost.
Scientists used a special climate model to simulate the processes of temperature changes on the ground. The results show that if greenhouse gas emissions are left unchecked, soil temperature could rise 3.8 ° C by 2100, melting half of its permafrost. However, with the ungulate relocation method, the soil heats only 2.1 ° C (less than 44%), which helps maintain 80% of the permafrost.
The team is examining the potential side effects of the method, for example, in the summer, whether these herbivores destroy moss and insulating vegetation, causing soil temperature to rise or not. In the next phase, they want to work with biologists to find ways to expand the range of ungulates in the Arctic.