Vast areas of Stretching across the far north of our planet, peat is an accumulated organic matter that is too wet to decompose. Although peatlands represent only 3 percent of the total land area, they store a third of terrestrial carbon. And they have climate scientists worried: As the Arctic warms, they are drying up and releasing huge amounts of carbon. People are speeding up this process by drying up peatlands and turning them into agricultural fields, releasing more greenhouse gases.
lately paper in the magazine science progressThe researchers put together a huge number of climatic influences for agriculture in these areas: By modeling historical land use, they calculated that between 1750 and 2010, northern cultivated peatlands released 40 billion tons of carbon.
“When the peatland dries up—that is, people dig drainage channels to lower the water level in the peatland to make it suitable for growing crops—the peat soil is aerated and aerobic microbial decomposition of organic matter that needs oxygen is enhanced, thus releasing carbon from the peat into the atmosphere,” Lead author Chunjing Qiu, from the Laboratory of Environmental and Climate Sciences in France and the University of Paris-Sclay, wrote in an email to WIRED. Any new plant matter that grows and dies there will quickly decompose, releasing its own carbon, because there is not enough water to slow down the processing of organic matter into carbon dioxide.2.
Traditionally, climate scientists have focused on how much carbon we might lose from deforestation, but they haven’t often looked at the effects of converting peatlands into fields. “We haven’t always done a good job calculating how much carbon might be lost from Soil Soil scientist Maria Strack, who studies peatlands at the University of Waterloo, but was not involved in the research, says. “In particular when we convert peatlands to cropland, the size of the soil organic stock is so large that we may have really underestimated the contribution of soil carbon losses to greenhouse gas emissions.”
So humanity is turning a critical carbon sink into Source of emissions. There are, of course, basic social drivers for this shift: As populations continue to grow, nations must feed more people with the same amount of land. Economically, it makes sense for farmers to convert what were previously sod areas into farmland. “It creates perfectly fertile soil, but at the same time you lose carbon,” says biogeochemist Chris Evans of the UK Center for Environment and Hydrology, who was not involved in the new paper. “Because a lot of carbon is lost from some of these landscapes, it’s kind of an empty carbon storage unit, really.”
Agricultural operations only accelerate this loss. Plowing dry peat allows more oxygen to penetrate, which also encourages the processing of organic matter into carbon dioxide.2. The microbes responsible will multiply even more if farmers add fertilizers that provide them with additional nutrients. In moist, healthy peatland, the plant matter it produces must stick around and, once it dies, is incorporated back into the moistened soil, where its carbon will be sequestered for thousands of years. But on the farm, the crops produced by the land are uprooted from the land and plucked for sale.
Farmers working on actively cultivated peatlands will water it, keeping the soil at least moist enough for plants to grow. But if the land is later abandoned and left to dry out completely, it will turn into a gruesome fuel for wildfires. Because peat is concentrated carbon, it burns easily – but not like the wildfires you’ll see. California or Australia. Instead of producing flames, peat is burned, burning deep into the ground and moving laterally across the landscape. Peat fires are such continuous fires that they can survive underground through the winter with snow falling on top of them, only to Pop up again When the landscape thaws in spring. That’s why they are called by scientists zombie fires. They can release 100 times the amount of carbon That a fire above ground might be.
Nature is also drying up the peatlands on its own as the northern lands are rapidly warming. The North Pole as a whole greening As a vegetable march north due to climate change. Warmer temperatures mean thunderstorms are becoming more common, providing sparks to ignite huge peat fires: By 2100, lightning strikes in the far north can double.
So, it is very important to restore the peatlands that were previously cultivated by farmers. “Not only will you reduce your emissions from oxidation, you will also reduce your fire risk,” says Strack.