Too much snow bad for Arctic plants: new study

Heavy and prolonged snowfalls can bring about unexpected conditions that encourage mold, leading to the death of plants in the Arctic, according to new international study.

Its results, published in the journal Nature Climate Change, show the long term effects of unexpected fungal development in the Arctic, where more snow is predicted as the climate warms, a June 19 news release said.

During the seven-year experiment, researchers observed steady plant growth under the protection of the snow’s insulating blanket.

But in year six, a fungus, similar to the kind of mold found on a stale piece of bread, spread rapidly, killing the plants.

While snow has an insulating effect, helping plants to grow bigger, heavy and prolonged snow can also encourage the rapid and extensive growth of killer fungal strains, researchers involved in the study say.

“We were surprised to find that this extremely hardy tundra vegetation was killed off by fungal attack,” said Dr. Robert Baxter from Durham University in the UK. “In the first few years, as expected, the insulating effect of the snow helped the vegetation to grow, but after six years a tipping point was reached where the fungus spread with great speed and destroyed the plants”

For their research, scientists compared the effects of normal snowfall conditions and increased snow conditions on vegetation in northern Sweden.

They used snow fences to maintain increased snow conditions, and found that the presence of a certain kind of fungus, or mold, increased under heavier and prolonged snow cover.

The fungus killed the majority of the shoots of a small shrub, one of the dominant plant species in that area.