You seem to have frame it as “land destroying plant only farming” vs “animal and land friendly mixed use” which seems like a false dichotomy. What’s wrong with plant based + rotating crops and sustainable use?
(I eat meat, fwiw)
Plant -> Person
Plant -> Farm Animal -> Human
Edit: My goal is to explain the basics of the argument that the parent comment was unfamiliar with, not to advocate.
You’re saying animals are extra steps and I’m saying both plant alone or mixed use could be sustainable?
There are worrying signs. Maybe the largest is the amount of deforestation happening to support the growing beef industry and feedstock for animal agriculture [0].
[0] https://www.worldwildlife.org/magazine/issues/summer-2018/ar...
The effect of this on your diagrams is in diagram 2, with the intermediate farm animal, there are many situations in that scenario where the calories from those plants would be entirely lost, not simply rerouted losslessly to human consumption.
It seems to me that there are many grassy hills that cannot be farmed using tractors and to farm them using hand tools is too labor-intensive.
My knowledge comes from exposure to the agricultural industry. You might be able to find some animals grazing on a grassy hill, but that doesn't scale. In addition, most NA climates don't support year long grazing.
This fundamentally ignores a bunch of realities around land quality, thermodynamics, and nutrition bio-availability.
Generally what's wrong with (everything in the nutrtition and fitness space) that the terms are overloaded to mean whatever it is the person speaking it deems at the time. Example: Paul Saladino (carnivoreMD) touts an animal based diet. Then when you dig into what he really recommends for eating is animal products + fruits and plants that have limited defense chemicals that can cause (for some people) disruptions in their life.
The position i advocate for is regenerative agriculture where we sequester more carbon by using the animals to mimic the natural grazing cycles and provide fertilizer for plants. This is incredibly important because in order to produce crop yields like we do, we require massive amounts of fertilizer, which requires petroleum inputs to create which gets us back to thermodynamics. To do crop rotation appropriately in a sustainable way, you need ruminant animals.
It's a complex topic that I invite everyone to spend some time taking a look at because there's really big money in meat production as well as artificial meat production that have a vested interest in winning you over.