As more of the world’s forests are destroyed, it makes you wonder: what’s going to absorb CO2 in their place?! In an ironic twist of fate, one of Earth’s “deadest” habitats might be our best hope for an ongoing supply of breathable air.

Called peatlands, these wetland environments are named for their tendency to accumulate decayed plant matter. Unlike most other ecosystems, like forests, where branches and leaves typically decompose in a matter of months… in peatlands, that plant material can stay intact for millenia. You see, peatlands mostly exist in high altitude places where temps are low and there’s not much water flow. This results in their having extremely low oxygen and high acidity levels.

These harsh conditions aren’t very hospitable to microbes and fungi, which are instrumental to the whole decomposition process. So without them around, the plant material sort of… just sits. Over time, that it globs together to form peat, a thick, spongy material that can soak up 20x its weight in water. Peat also soaks up loads of carbon. Through a process known as the Calvin cycle, living plants absorb CO2 from the air and convert it into organic molecules that they can then use as energy to grow.

Through decomposition, the carbon that’s “fixed” in a plant’s structure gets released but since peat doesn’t decompose, that carbon can stay put! It’s estimated that peatlands contain 550 gigatonnes of organic carbon, which is twice as much organic carbon as all the world’s forests combined. That’s absolutely wild, considering that forests cover about 30% of the world’s land area… and peatlands only account for 3%! Like most of the world’s habitats, peatlands aren’t immune to the threats of human development and exploitation.

Peat is also are a very in-demand resource. Its incredible water holding capacity makes it a favorite amongst horticulturists; If you’ve ever picked up a bag of soil amendment, chances are it’s full of the stuff. Since peat is also a fossil fuel with a long burn, it’s used in some parts of the world. Peatlands are also often drained to accommodate other land use activities, like agriculture.