Placeholder Image

字幕表 動画を再生する

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

    こんにちは、ケイトです。

  • dirt.

    命を支える土を 私たちが「無価値なもの」とみなすのは

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

    放っておいても 自然に生まれるから。

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

    動植物の死体や、岩の分解で

  • water erode it away

    風や雨で流れ去ったぶんの土が 補充されるからです。

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

    でも、このバランスは たやすく崩壊してしまいます。

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

    2,000年前、太平洋はマンガイア島の 豊かな薄い土壌を

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

    やってきた人間の焼畑農業が 風雨にさらしました。

  • exposed the soil to the elements.

    続く数世紀で、島の斜面は 栄養豊富だった表土を失い

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

    土の残された、わずかな谷間をめぐって 人々は争います。

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

    作物がとれないので 彼らはネズミを食べ

  • viciously fought over.

    共食いも起きました。

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

    私たちも、同じことをしています。

  • even each other.

    農業で、土の流出を 引き起こしているんです。

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

    私たちの農業は 深く根を張る木を取り去り

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

    土を耕して、ゆるめてしまうので

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

    土は、雨や風に 弱くなってしまいます。

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

    根の浅い作物に 土を留める力はありませんし

  • to sweep away.

    収穫後の土は はだかの状態で残されます。

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

    このため世界の耕作地では 生成される50倍の速度で、土が失われます。

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

    小型トラックが、年に80億回 畑の土を運び出し

  • mercy of the elements

    川やダムの底に 捨てているようなもの。

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

    カリフォルニアの1/10サイズの耕作地を 毎年無駄にしているのと同じことです。

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

    土の生成と流出の バランスをとることは、可能です。

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

    耕す回数を減らしたり

  • for farming.

    刈り取った後の茎や葉、または 「被覆作物」で、土を覆えばいいんです。

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

    畑に木を植えて 土を守ってもらうこともできます。

  • swath of farmland out of production every decade.

    これらの取り組みは 土の流出を95%も減らし

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

    持続的な農業の 助けになります。

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

    ただ、畑の面積を割くこの方法は 短期的な生産量は落ちるので

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

    十分に実施されていないのが現状です。

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

    畑の土が減っていっても 人類がすぐに絶滅するわけではありません。

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

    でも、土をめぐる争いは 起きるかもしれません。

  • keep crop yields high in the long run.

    マンガイア島より ずっと大きなスケールで。

  • 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

こんにちは、ケイトです。

字幕と単語

動画の操作 ここで「動画」の調整と「字幕」の表示を設定することができます

B1 中級 日本語 農業 作物 減らし バランス 土壌 浅い

How To (Literally) Save Earth

  • 4 2
    joey joey に公開 2021 年 04 月 30 日
動画の中の単語