土壤无疑是很多生命的根基 然而我们却视土壤为……嗯 像是
Soil is the literal foundation for much of life, yet we treat soil like… well, like
Maybe that’s because, most of the time, soil takes care of itself
通过分解动植物 和降解基岩 以形成新的土壤
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 rats—and
even each other.
We are 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
然后用锄头 棃 拖拉机来松土
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 soil 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.
他们最新的产品Coffiest 一种咖啡口味 富含藻类的瓶装食物 重新定义了早餐
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.
土壤无疑是很多生命的根基 然而我们却视土壤为……嗯 像是