Just as a good wool blanket will keep a human baby warm and healthy, a white spruce baby will also be protected from snow blankets. At the same time, the blanket of snow helps thaw permafrost, frozen soil packed with ancient plant matter and ice, by preventing winter cold from reaching the ground. Generally, this top layer of permafrost thaws in the heat of summer and refreezes in winter. However, if there is enough snow on top, the soil will not cool down as much and the microorganisms that break down the organic matter in the permafrost will become more active.
It in turn releases the nutrients those dead plants have themselves It had been absorbed long ago. “When you get closer to open ocean areas like the Chukchi Sea, there’s more nitrogen, and both adults and juveniles grow faster,” says Dial. And there were more of these teenagers around the adults. ”
Not only do white spruce seedlings enjoy a warm, cozy blanket of snow, but they’re also basically bottle-fed with the nutrients they need to grow and produce cones and seeds that spread beyond the current tree line. It is ingested from. “Seed production, germination, and establishment of new plants are what drive the progression of the tree row,” Sullivan says. “When we get more snowfall and the wind blows over that ground, the trees tend to act like snow fences themselves, and the snow tends to accumulate under the trees.” This provides even more insulation.
“This is a really impressive analysis that goes far beyond the simple relationship that people have long assumed is that temperature is a big factor in treeline progression,” said Scott Goetz, NASA’s chief scientist. Arctic Vulnerability Experiment, was not involved in the study. “I think this is a big step forward.”
As you can see from these photos, we are not yet talking about dense, full-fledged forests, but rather pioneers, the beginnings of larger boreal tree populations. Still, as the trees grow, they darken the landscape and absorb more solar energy than pure snow, which reflects sunlight back into space. This increases local warming, thaws permafrost, and increases the number of trees. Not only does permafrost release more nutrients to grow more trees and shrubs (a kind of self-perpetuating feedback loop), permafrost also releases greenhouse gases, driving further warming. Masu. Microorganisms that feed on ancient plant material release carbon dioxide and methane as byproducts. .