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  • This video is sponsored by Brilliant.

  • When Alan Savory gave a TED talk in 2013, he  captivated the world. Savory's speech cut right  

  • to the point: climate change, overpopulationand desertification threatened to swallow the  

  • human world if left unchecked. But what delighted  Savory's audience, as well as a number of the 4.3  

  • million viewers on YouTube, was not this dire  forecast, but rather Savory's solution to the  

  • problem: eat more meat and graze more cattleThat's right, Savory outlined a win-win scenario  

  • wherein if we just grazed more cattle in  a very specific way, we could potentially  

  • turn back the tides of desertificationsequester carbon, and stop climate change.  

  • Which to me, in 2013 sounded great. Exceptas I later learned, Allan Savory was wrong.  

  • This is the story of grassfed beef and rotational  grazing. How it came to be this win-win solution  

  • to climate change, and how the hype around  its implementation is, well, just plain wrong.

  • Grass-fed beef will save the world?

  • Savory is not alone on his quest to  proselytize the good word of beef.  

  • Michael Pollen, in his book The Omnivore's  Dilemma, gushes over Joel Salatin's intensive  

  • grazing techniques at Polyface farms, and even  two years ago, I suggested in a video about going  

  • vegan, that rotational grazing systems had the  potential to mitigate climate change. Of course,  

  • not all grass-fed beef is rotationally grazed  beef, and indeed rotational grazing practices  

  • can vary from farm to farm. One rancher  might only rotate their cows every 2 months,  

  • while another might rotate them every dayIn general, grass-fed beef can be seen as an  

  • umbrella term for a variety of grazing systemsunder which rotational or regenerative grazing  

  • operations are considered the gold standard  and are lauded as possible climate saviours.  

  • The core belief behind all of these regenerative  systems is that by constantly moving high numbers  

  • of cattle from one plot to the next, the cows  will indiscriminately eat up plants--shocking  

  • them into growing deep roots. And when the  plants eventually die, these roots will lock  

  • carbon into the ground. Regenerative grazing  proponents also claim that livestock help  

  • sequester carbon with their manure, as well as  by breaking up the soil crust with their hooves  

  • and burying carbon in the dirt where it is less  prone to re-release. The result of all of this  

  • carbon sequestration, regenerative ranchers claimis that these systems suck more greenhouse gases  

  • out of the air than cows emit through belching  and manure. Essentially, regenerative grazing  

  • acts as a carbon sink that heals the soil and  sucks greenhouse gases out of the air. And there  

  • have been a few studies that support this carbon  sequestration hypothesis. In the Upper Midwest,  

  • one study found that high-rotation grazing did  indeed store more carbon then the cows created.  

  • But here's the thing: these papers are outliers  in a vast body of academic work on the subject.  

  • As we'll see soon, these claims are mostly  unfounded, have better alternatives, and when they  

  • do work, often represent best-case scenarios with  perfectly managed systems in the perfect setting.

  • Why beef can't save the world

  • Despite Savory's beautiful pictures and convincing  rhetoric of regrowth and grazing, his claims have  

  • been heavily criticized for a lack of scientific  evidence. Keep in mind, this is the same man,  

  • who in 1969, argued for the massacred 40,000  elephants in Zimbabwe because he thought they were  

  • ruining their own habitat. Even Joel Salatin knows  that his farm is not that sustainable: “Actually,  

  • everyone else calls us a sustainable farm. I  don't call us a sustainable farm, because at  

  • the end of the day I really don't think we should  be raising the number of broilers that we raise,  

  • for that very reason.” In a comprehensive analysis  of the scientific research on rotational grazing,  

  • The Food Climate Research Network found that  grazing systems only sequester around 20-60%  

  • of the emissions from livestock. In additiongrasslands can often reach a carbon storage  

  • equilibrium within a few decades. Which means that  the soil's ability to sequester carbon slows over  

  • time and then eventually stops. Essentially, soils  are not just some bottomless pit in which carbon  

  • can be endlessly stored. So, when the soil reaches  that equilibrium point the cattle still grazing  

  • on the land will most definitely be creatingnet addition to greenhouse gas emissions in the  

  • atmosphere. Research and conventional wisdom also  shows that grass-fed beef requires more and older  

  • cows than feedlot finished beef. This is because  grazed cows get a lot more exercise and fatten  

  • up much slower than their kin in feedlots. The  end weights of grazed cows are generally lower,  

  • and the time it takes to get them to that weight  is longer. All this means that cows have more  

  • time to emit greenhouse gases when grazedAnd finally, regenerative grazing techniques  

  • require a lot of land. Right now, grazing-only  ruminants contribute just 1g of protein per person  

  • per day in the global protein supply. And yetdespite contributing a negligible amount to the  

  • global protein mix, livestock grazing uses 26%  of liveable land. Oh and beef production is the  

  • number-one driver of tropical deforestation  in South America. So regenerative grazing,  

  • while good in theory, on the ground fails to live  up to its hype. If scaled up, it would require  

  • massive tracts of land and could potentially  create more emissions than it prevents. Indeed,  

  • in terms of the climate, it could be dangerous to  pursue regenerative grazing, especially when there  

  • are perfectly sound alternatives that are known to  sequester carbon and create far fewer emissions.

  • What should we do?

  • So if grass-fed beef and rotational grazing  methods won't mitigate climate change,  

  • then what should we do? Let's consider what  would happen if we didn't need grazing lands for  

  • livestock. We could instead implement  reforestation, aforestation, and rewilding plans  

  • that over time could potentially lock up way more  carbon than grazing systems. And vegetable-based  

  • farming systems like the no-till, compost-heavy  operation at Singing Frogs farm in California,  

  • demonstrate that it's possible to sequester carbon  without using cattle. But there are still over 200  

  • million people who rely on grazing as a source  of financial and nutritional stability. For them,  

  • a transition to rotational grazing systems must  be a start, but a full transition away from a  

  • meat-based economy has to happen to dramatically  reduce emissions, which means ranchers and cattle  

  • farmers across the world need ample support  from governments to facilitate that transition.

  • But, this would also be a transition for  consumers. Cutting out meat is one of the  

  • most effective and achievable personal solutions  to climate change. Project Drawdown models that if  

  • 50% of the world adopted plant-rich diets  we'd be able to avoid 65.02 gigatons of  

  • carbon dioxide-equivalent gases by 2050,  which is about the same impact that removing  

  • every single form of transportation from the  earth for nine years would have. But Americans  

  • in particular eat a lot of meat, and it's  challenging to stop buying animal products  

  • in a world where a full meat-based meal is often  cheaper and easier to access than produce or meat  

  • alternatives. Which means that government  must also subsidize and promoting the  

  • practices of operations like Singing Frogs Farm  or vegetable farms in neighborhoods experiencing  

  • food apartheid. Because, at the end of the dayfostering food systems that create access to  

  • nutritious and pleasurable plant-based food means  fostering food systems that protect the climate.

  • This video took a while to research because  there's so much out there on grazed beef.  

  • But honestly, that's one of my favorite parts  of the creation process. I love diving into  

  • educational content, which is why I'm  constantly recommending Brilliant. It's a  

  • website and app that uses problem-solving and  active learning to make learning accessible  

  • and fun. Brilliant is all about seeing  concepts visually and interacting with them,  

  • and then answering questions that get you to  think. Their courses are laid out like a story,  

  • and broken down into awesome visual pieces so that  you can tackle them a little bit at a time. Take,  

  • for example, Brilliant's completely revamped  course on the fundamentals of Geometry. I was  

  • terrible at Geometry in school, but Brilliant  laid out the ideas behind angles, perimeters,  

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  • This little interactive triangle is a perfect  example. By changing the side lengths,  

  • we can easily see that the sum of the  triangle's internal angles is always 180.

  • But Charlie, what if I get something wrongWell, with Brilliant, there's no tests and  

  • no gradesif you make a mistake, no big dealYou can just check out the handy explanations  

  • to find out why you messed up, which for mehappens often. You can learn at your own pace,  

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  • the first 200 people that go to that link will  get 20% off their annual premium membership.

  • Hey everyone, Charlie here. This video, as alwayswas made possible by my patreon supporters.  

  • They donate a couple of dollars each month  to help me grow and build this channel  

  • so it can reach an even bigger  audience. Thank you so much to my  

  • patreon supporters and thank you for  watching! I'll see you in two weeks!

This video is sponsored by Brilliant.

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B2 中高級 美國腔

草食牛肉的问题(The Problem With Grass-Fed Beef)

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    joey joey 發佈於 2021 年 06 月 12 日
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