By eating vegetarian you cut one or maybe several factors of ~ 0.1 out of the equation. I'm not vegetarian but have reduced my meat consumption by a lot while not having the feeling that I miss anything.
https://en.wikipedia.org/wiki/Trophic_level#Biomass_transfer... https://en.wikipedia.org/wiki/Ecological_efficiency#Ten_perc...
https://www.nhs.uk/live-well/eat-well/vegetarian-and-vegan-d...
I believe cutting back on meat would still be a significant improvement over the current situation.
Edit: I was not talking about missing vitamins when I said "missing". I was talking about missing something as in suffering from practising self-denial.
Its complicated, but not eating meat would account for somewhere between 3-8% reduced greenhouse gas emissions. And as more of the world's population becomes "first world" demand is going to go up unless we start reducing cultural dependence on meat throughout our diets.
Meat is significantly less efficient to produce than a balanced vegetarian diet.
That entirely depends on the land, no?
Sheep and goats can thrive on land you can’t actually use for any other sort of farming. We have lots of that land here in Wales.
The most sustainable way to farm would be to open pastured cattle, pigs, and sheep which would drop manure in a fallow field and add tons of organic nutrients to the soil - as happens in nature. That pasture would then be used to grow crops the next year, as the animals are rotated to another area. When an area is only used for growing vegetables, there is a net depletion of natural nutrients that have to be supplemented with external input.
The worst part of agriculture is farming ONLY beef or ONLY dairy or ONLY vegetables on acreage. I'm going to risk being contrarian to the HN crowd - but farming can't be automated in a sustainable way. The ecosystem is far too multivariate and interrelated. Sure, you can make a smarter tractor, but that land will be barren in 40 more years. Automation only works at scale, but nature does not divide into neat discrete categories without some sort of tradeoff in biodiversity or long-term resilience
It only takes a few passes with a plow to turn it into desert, so pretty much the only way of getting calories from land in Montana is by grazing cattle or bison.
Kind of irrelevant though, ranch land in Montana only support a few cattle per square mile.
I don't know enough about Montana, but I'm mostly worried about what monoculture farms are doing to the fertility of the Midwest.
True. Unfortunately the majority of meat does not come from grass fed animals.
Particularly organic vegetarian diets need a lot of land.
Here is a land use graphic from Our World In Data that also includes information on what fraction of consumed calories and proteins are provided by the uses.
https://ourworldindata.org/uploads/2013/10/Land-use-graphic-...
This graphic is used in the article https://ourworldindata.org/yields-and-land-use-in-agricultur...
My concern is that we don't have enough land for this, and the fear/threat of overpopulation is already upon us. And has been for decades.
Consider that all of the land currently used for livestock were converted. You then _also_ have all of the land used for feedstock for the livestock.
And then there's the fact that most diets globally are predominantly vegetable based anyway - meat is a rare addition.
You can't convert it, or it's already converted. Usually for corn.
The animals we eat are mostly fed by what is cultivated on the arable land, exactly because of the modern habits of everybody eating meat every day. Most of the animals never see the pastures. The demand is too big and getting much bigger.
So we feed the animals, and most of the energy stored in their food is converted to the maintenance of the life of the animal, not the meat you get when you kill it.
Compare that with feeding the humans directly (with mostly vegetarian diet): most of the animal food you grow, transport and feed to the animals never end up becoming meat.
See for example:
https://iopscience.iop.org/article/10.1088/1748-9326/11/10/1...
Example from ten percent law [0]:
> Sun releases 1000 J of energy, then plants take only 100 J of energy from sunlight; thereafter, a deer would take 10 J from the plant. A wolf eating the deer would only take 1 J. A human eating the wolf would take 0.1J, etc.
We can go directly from plants to people instead of using land, energy and resources to grow plants to feed animals for human consumption with 10% efficiency.
[0] https://en.wikipedia.org/wiki/Ecological_efficiency#Ten_perc...
The only way that meat could win on either metric is if livestock are able to subsist on a diet far less varied than humans; essentially if they are better able to convert lower quality feedstock into higher quality meat.
Our baseline should be what is required for a healthy body and brain. We can go up from there.
Going down from the current level is farcical. We're in a crisis.
I like me an avocado as much as the next person, but if they need a 500% tax (invented, I don't actually know) to incorporate externalities, they need it. End of.
Like, seriously. It doesn't matter what we "want" at this point. Carbon needs pricing or we are totally fucked.
No, because livestock need food too and are horribly inefficient at turning food/water into meat.
Anyway it is a worthy goal but people shouldn't think they are doing their part of they are successful. I believe the numbers are that if all cows disappeared tomorrow, that'd take care of something like 5% of our worldwide carbon-equivalent emissions.