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  • Soil is the literal foundation for much of life, yet we treat soil like... well, like

  • dirt.

  • Maybe that's because, most of the time, soil takes care of itself; decomposing plants and

  • animals and degrading bedrock produce new soil at roughly the same pace that wind and

  • water erode it away

  • But this balance between soil formation and erosion is easily tipped.

  • For millennia, the tiny Pacific island of Mangaia was covered in a thin layer of fertile

  • soil, but after humans arrived around 2000 years ago, their slash-and-burn agriculture

  • exposed the soil to the elements.

  • Over several centuries, rain and wind swept virtually all the nutrient-rich topsoil from

  • Mangaia's hillsides and concentrated it in just a few arable valleys, which people

  • viciously fought over.

  • With less land to grow crops, people resorted to alternative food sources like ratsand

  • even each other.

  • We're doing the same thing throughout the world today - not the part where we eat each

  • other, but the part where we farm the soil away.

  • That's because we make for agriculture by clearing away deep-rooted native vegetation

  • and use hoes, plows, and tractors to loosen the soil, making it easier for wind and rain

  • to sweep away.

  • And we grow mostly shallow-rooted crops that are no good at holding onto soil, and that

  • get stripped away during harvest, leaving fields bare for much of the year and at the

  • mercy of the elements

  • As a result, the world's farmlands lose soil 50 times faster than new soil can form.

  • That extra erosion adds up to about 8 billion pickup trucks of soil moved annually from

  • fields to places like the bottoms of rivers and behind dams - which are less convenient

  • for farming.

  • That soil loss reduces global crop yields by as much as if we took a California-sized

  • swath of farmland out of production every decade.

  • Fortunately, we know how to bring erosion back into balance with the rate at which soil

  • forms: plow less often, and after harvest, leave plant parts behind or plant so-called

  • cover crops to, well, cover the soil as protection against water and wind.

  • We can also incorporate trees or native plants that keep soil in place year-round.

  • Putting strategies like these in place can cut erosion by as much as 95 percent, helping

  • keep crop yields high in the long run.

  • But in the present, they can hurt yields, because adding other vegetation to farm fields

  • means less room for crops.

  • As a result, we've been slow to make these soil-saving strategies the norm.

  • If we can't keep the farmable soil on our farms, human civilization won't immediately

  • implode, but we might end up fighting over the patches of land where that soil ends up,

  • like the Mangaians, but on much, much bigger islands.

  • And, speaking of soil, this video was sponsored by Soylent, a line of nutritionally-complete,

  • convenient foods that actually take less Soy-l to produce because many of their core nutrients,

  • including omega-9 fatty acids, come not from plants grown in fields but from algae grown

  • in fermentation tanks.

  • Their newest product, Coffiest, reimagines breakfast as a coffee-flavored, algae-fueled

  • meal in a bottle to help kickstart your day.

  • Plus Soylent has partnered with the World Food Program USA to donate a meal to someone

  • in need for every case of Coffiest they sell.

  • Go to soylent dot com slash earth, that's s-o-y-l-e-n-t dot com slash E-A-R-T-H or click

  • on the link in the description to get 10% off of your first month's worth of Coffiest.

  • Thanks, Soylent!

Soil is the literal foundation for much of life, yet we treat soil like... well, like

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B1 US soil erosion wind slash vegetation algae

How To (Literally) Save Earth

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    joey joey posted on 2021/04/30
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