Name: 草食牛肉的问题（The Problem With Grass-Fed Beef）
Uploaded: 2021-06-12T11:43:54.000Z
Duration: 10 min 37 s
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When Alan Savory gave a TED talk in 2013, he  captivated the world. Savory's speech cut right  

to the point: climate change, overpopulation,  and 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 cattle.  That'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 desertification,  sequester carbon, and stop climate change.  

Which to me, in 2013 sounded great. Except,  as 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.

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 day.  In general, grass-fed beef can be seen as an  

umbrella term for a variety of grazing systems,  under 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 claim,  is 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.

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 addition,  grasslands 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 creating a  net 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 grazed.  And 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 yet,  despite 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.

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 day,  fostering 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,  

and coordinates in such an intuitive way that  it made Geometry actually kind of fun to learn.  

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 wrong?  Well, with Brilliant, there's no tests and  

no grades — if you make a mistake, no big deal.  You can just check out the handy explanations  

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

and there's something for everybody — whether  you want to brush up on the basics of algebra,  

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

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