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  • Trees, deservedly, get lots of credit for recycling carbon dioxide into oxygen for us to breathe.

  • So 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 “deadesthabitats might be our best hope for an ongoing supply of breathable air.

  • Bogs. Swamps. Fens.

  • 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 millennia.

  • 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 “fixedin 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 youve 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.

  • Since the 70s, weve lost over one-third of the world’s peatlands.

  • This poses a fair number of problems, as a lower water table can cause the land to sink,

  • increasing the risk of flooding.

  • And since peatlands tend to absorb heavy metals and contaminants, if theyre drained,

  • those toxins get released into the air.

  • I mean, imagine how many thousands of years worth of stuff is locked away!

  • The many mammals, migratory birds, amphibians, and insects that rely on peatlands for habitat and food are displaced.

  • And what’s more, dried-out peatlands are more vulnerable to fires

  • which until recently, were extremely rare.

  • Because peatlands are so carbon-rich, fires burn with such intensity that they can be near-impossible to put out.

  • These so-calledzombie firescan persist underground even in the dead of winter!

  • And when peatlands burn, guess where all that carbon is going: back into the atmosphere.

  • Annually, CO2 emissions from damaged and drained peatlands total roughly 2 gigatons.

  • And as the climate continues to warm, this number is only expected to climb.

  • But work to restore peatlands to their full carbon-storing potential is underway.

  • In 2016, the UN launched the Global Peatlands Initiative to mobilize governments to restore these vulnerable ecosystems.

  • And in some parts of the worldlike in Scotlandefforts are really paying off.

  • Restoration of 25,000 hectares is already in motion

  • and the govthas pledged to fund work on another 250,000 hectares by 2030.

  • This work often involves covering parts of exposed peatland, slowing the flow of water, and reducing drainage...

  • but can also involve revegetation, particularly if the land was burned, and changing existing zoning laws to prevent cultivation.

  • Given their massive potential to lock away carbon,

  • making the protection and restoration of the world's peatlands a high priority

  • right up there with reforestation

  • makes sense.

  • Because as we scramble to reckon with the climate crisis,

  • making use of ALL of the solutions out there, rather than focusing on a flashy few

  • will be our best bet for wading through the bog.

  • Peat bogs aren’t just able to store carbon for millennia

  • theyre pretty good at storing the remains of people too!

  • Thesebog bodieslook like mummies and can provide archaeologists with clues as to how people lived in the past.

  • Some bodies are so well intact that they can have their fingerprints taken!

  • Pretty creepy, right?

  • Make sure to hit that subscribe button for all your climate news,

  • and thanks so much for watching Seeker. I’ll see you next time!

Trees, deservedly, get lots of credit for recycling carbon dioxide into oxygen for us to breathe.


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A1 初級

This Forgotten Ecosystem Holds Twice as Much Carbon Than Forests

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    Summer 發佈於 2021 年 10 月 04 日