https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5715743/

In the simulated system with no animals, estimated agricultural GHG decreased (28%), but did not fully counterbalance the animal contribution of GHG (49% in this model). This assessment suggests that removing animals from US agriculture would reduce agricultural GHG emissions, but would also create a food supply incapable of supporting the US population’s nutritional requirements.

Assuming agricultural emissions account for 9% of total US emissions (47), and assuming that emission estimates here are representative of national emissions, eliminating animal agriculture would decrease total US emissions by an estimated 2.6 percentage units.

There is a reason why we have different farming, because of different soil quality.

So the effect would be to reduce the area of where we can produce food.

And if you would remove cattle you no longer have natural fertilizer. Mineral fertilizer has a big environmental impact on ground water.

> The thing is that soil used for grazing cattle can’t be used for planting vegetables efficiently.

Not planting vegetables efficiently != not planting them at all, right? Could the lower yield on such fields still come ahead of lower energy efficiency of meat (in terms of energy expended per calorie of final human food produced)?

> So the effect would be to reduce the area of where we can produce food.

Surely we can grow something human-edible there. Or could perhaps this land become earmarked for construction, while equivalent amount of very fertile land could be switched from construction to farming? AFAIK there's plenty of settlements built on land that would be better used for farming.

> And if you would remove cattle you no longer have natural fertilizer.

Is industrialized agriculture even using natural fertilizer? I was under impression modern fertilizers are made in chemical plants and their production doesn't involve animal excrement.

Cattle can transform grass, that we can't eat, to protein that we need. It is actually a good thing, especially if you can't grow anything there.

In Sweden we have something called ecological farming, it is certification, to be approved for ecological farming you can't use mineral fertilizers anywhere in your food production.

Ecological products are usually somewhat more expensive in the store.

Now there are of course lots of farms that is not classified as ecological and they can use mineral fertilizers or natural fertilizers.

About a third of all fertilizers for farming used in Sweden is natural.

> If it is not efficient it will cost more than it yields, a loss.

I was thinking about less efficient, but still profitable. I presume it's not a binary, and farms aren't operating barely above EROI of 1.

> According to FAO 70% of worlds land surface is not suitable for planting crops.

That's... super surprising to me. I would have expected something closer to 50-40%. Perhaps it hinges on the definition of "suitability"? I'll look into those stats.

> About a third of all fertilizers for farming used in Sweden is natural.

That's also surprising to me. Is this number so large because there are so many ecological farms in Sweden, or natural fertilizer is just so popular?

With more being produced within your country you can legislate higher requirements on production methods. And when food becomes more expensive to buy, the incentive to have high quality production increases.

In the west we no longer have the problem of food shortage, thus we can afford somewhat higher food prices. And of course if you produce more within your country, you can get better salaries.

Why Sweden uses that much natural fertilizer I can't really tell.

But I found something about high prices on synthetic (mineral or others like natural gas) fertilizers. This was something that started happening globally around 2008. Between September 2007 and September 2008 prices increased with 80 percent globally.

If you understand Swedish, 2008

https://www2.jordbruksverket.se/webdav/files/SJV/trycksaker/...

Isn't corn production massively subsidized in the US? So it becomes cheaper to feed cattle with corn instead of grazing. Madness.

That type of meat production is not something I support.

http://www.worldstopexports.com/top-beef-exporting-countries...

Interestingly, the #1 exporter, Australia, has historically used a mix of grazing and feed grains. But they're expecting to grow more feed grains because grazing suffers during droughts, which are increasingly common. Apparently those grains are wheat and barley; corn is definitely an American obsession. I assume that will be grown on land that could otherwise be used to grow food for humans.

https://www.beefcentral.com/lotfeeding/grain-sector-faces-ne...

This is true, but it's not how modern meat is produced. A lot of high-quality land is used to produce meat that could be used to produce vegan food, no?

Grazing systems supply about 9 percent of the world's production of beef, the rest are crop fed in addition!