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I'm Annie Sneed.

The Arctic's permafrost is melting and fast. That's bad news because these frozen soils store billions

of tons of carbon just waiting to be unleashed. So is there a way to save the permafrost?

One team of researchers thinks that may have found a possible solution.

Big animals.

Herbivores.

Animals that eat only plants.

Back in 1996, researchers started an experiment called

Pleistocene Park. They fenced in about eight square miles of land in

northeast Siberia and then they introduced different types of herbivores,

reindeer, horses, moose, bison, sheep, and other large critters.

Since then, scientists have studied these animals effects on the ecosystem.

One outcome is that these large herbivores help keep the ground very cold,

cooler than it would otherwise be.

The snow in winter is important for soil temperature because it acts as an insulating

layer. So the air in winter in the highlage uses much colder than the soil.

Philip Perrada, a vegetation ecologist at the University of Hamburg.

So the idea of this experiment was to introduce large herbivores and to quantify their effects on soil temperature to see if they can actually protect

permafrost soils against thawing. And this works because the animals trampling leads to less insulation of the soil against the cold air temperatures and results in a cooling effect.

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