Can soil microbes survive sub-zero temperatures?

As we look out at the snow-covered fields of Zeeland Township, MI, on this cold February morning, it’s hard to imagine any living critters in the soil surviving the frozen west Michigan winter.

But somehow they do! And come spring, the microbes, worms, beetles and fungi will erupt with new activity, helping to produce new life on our farms and in our yards.

But how cold is too cold for the survival of soil life? Can microbes live in the Antarctic, where air temperatures regularly linger around -50 degrees Fahrenheit? The answer is– surprisingly– yes!

From the Soil Science Society of America:

Soils located in polar regions are unique to those found elsewhere, as they contain permafrost. Permafrost is a thick subsurface layer of soil that is frozen year round. In Antarctica, during the coldest parts of the year, the entire soil system is frozen solid. Because of this, the soil is actually very dry, like in deserts! If this is true, wouldn’t it be impossible for living creatures to survive there? Antarctica surely looks like a lifeless, barren area…
Amazingly, there is life in Antarctic soils. Even in these extreme environments, scientists have been able to find soil microorganisms alive and thriving.

What scientists have found is that these tiny organisms are able to survive by living in microscopic films of water that stick to soil particles (adherence). The bond energy between water molecules and soil particles is so great that it prevents the thin layer of water from freezing, even at extremely low temperatures. Microbes live in this unfrozen water, which allows them to stay alive even during the long deep freeze of winter.

These microbes aren’t just surviving, either. During the winter, they are still consuming organic matter, “exhaling” carbon dioxide (CO2) and maintaining their populations. They are actually alive, not even hibernating!
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You may wonder why scientists are willing to spend their time researching soil microbiology in such remote areas. Studying organisms in extreme and inhospitable environments like the Arctic and Antarctic allows scientists to make inferences about life on other planets. This type of research is also important for understanding how cold ecosystems function now, and how that might change in response to global climate change. Scientists are already starting to observe increased microbial activity in the polar regions. As temperatures rise, microorganisms are predicted to consume more soil organic matter, which could lead to the release of even more CO2 (a greenhouse gas) into the atmosphere.

Most of us don’t live in Antarctica, but in the northern parts of the hemisphere, it’s pretty cold in February. If you think you’ve got it bad, try to be inspired by the mighty polar microbes. They are some pretty tough organisms, and because of this, they can teach us very much.

At Good Sweet Earth, in order to more effectively treat lawns and gardens naturally and organically, we believe it’s important to fully understand soil and all of the life found within– even if that soil is found at the South Pole! That’s why we are members of organizations like the Soil Science Society of America. If you would like to put our knowledge and expertise to work in your yard this year, get in touch with us at [email protected].  Or check out the products and services we offer.

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